Doc. No. 101098C
October 26, 2000
SC56D Modem
V.90/K56flex
CX06827 Single Chip ACF Modem
with Optional CX20437 Voice Codec
Data Sheet
Conexant Proprietary Information
SC56D Single Chip ACF Modem Data Sheet
ii Conexant 101098C
Revision Record
Revision Date Comments
C 10/26/2000 Revision C release. Supersedes 101098B. Added power values to Section 1.2.1 and to
Table 3-12.
B 9/6/2000 Revision B release. Supersedes 101098A.
A 6/26/2000 Initial release.
© 2000, Conexant Systems, Inc.
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SC56D Single Chip ACF Modem Data Sheet
101098C Conexant iii
Contents
1 INTRODUCTION................................................................................................................................................. 1-1
1.1 Overview................................................................................................................................................... 1-1
1.2 Features ................................................................................................................................................... 1-4
1.2.1 General Modem Features .......................................................................................................... 1-4
1.2.2 Applications................................................................................................................................ 1-4
1.3 Technical Overview .................................................................................................................................. 1-5
1.3.1 General Description ................................................................................................................... 1-5
1.3.2 MCU Firmware ........................................................................................................................... 1-5
1.3.3 Operating Modes........................................................................................................................ 1-5
Data/Fax Modes................................................................................................................ 1-5
Synchronous Access Mode (SAM) - Video Conferencing................................................. 1-5
Worldwide Operation ........................................................................................................ 1-6
TAM Mode......................................................................................................................... 1-6
Voice/Speakerphone Mode (S Model) .............................................................................. 1-6
1.3.4 Reference Design ...................................................................................................................... 1-6
1.4 Hardware Description............................................................................................................................... 1-7
1.4.1 CX06827 Modem Controller and DSP ....................................................................................... 1-7
1.4.2 CX20437 Voice Codec............................................................................................................... 1-7
1.5 Commands ............................................................................................................................................... 1-7
2 TECHNICAL SPECIFICATIONS......................................................................................................................... 2-1
2.1 Serial DTE Interface Operation ................................................................................................................ 2-1
2.1.1 Automatic Speed/Format Sensing .............................................................................................2-1
2.2 Parallel Host Bus Interface Operation ...................................................................................................... 2-1
2.3 Establishing Data Modem Connections ................................................................................................... 2-1
Telephone Number Directory ............................................................................................ 2-1
Dialing ............................................................................................................................... 2-1
Modem Handshaking Protocol.......................................................................................... 2-2
Call Progress Tone Detection ........................................................................................... 2-2
Answer Tone Detection..................................................................................................... 2-2
Ring Detection................................................................................................................... 2-2
Billing Protection ............................................................................................................... 2-2
Connection Speeds........................................................................................................... 2-2
Automode.......................................................................................................................... 2-2
2.4 Data Mode................................................................................................................................................ 2-3
Speed Buffering (Normal Mode) ....................................................................................... 2-3
Flow Control ...................................................................................................................... 2-3
Escape Sequence Detection............................................................................................. 2-3
BREAK Detection.............................................................................................................. 2-3
Telephone Line Monitoring................................................................................................ 2-3
Send SPACE on Disconnect (V.22 bis and Below)........................................................... 2-3
Fall Forward/Fallback (V.90/K56flex/V.34/V.32 bis/V.32) ................................................. 2-3
Retrain............................................................................................................................... 2-3
Programmable Inactivity Timer ......................................................................................... 2-3
DTE Signal Monitoring (Serial DTE Interface Only) .......................................................... 2-4
2.5 Error Correction and Data Compression .................................................................................................. 2-4
V.42 Error Correction ........................................................................................................ 2-4
MNP 2-4 Error Correction.................................................................................................. 2-4
V.42 bis Data Compression .............................................................................................. 2-4
MNP 5 Data Compression ................................................................................................ 2-4
2.6 MNP 10 Data Throughput Enhancement ................................................................................................. 2-4
2.7 MNP 10EC™ Enhanced Cellular Connection .......................................................................................... 2-4
2.8 Fax Class 1, Fax Class 1.0, and Fax Class 2 Operation.......................................................................... 2-5
SC56D Single Chip ACF Modem Data Sheet
iv Conexant 101098C
2.9 Voice/Audio Mode .................................................................................................................................... 2-5
2.9.1 Online Voice Command Mode ................................................................................................... 2-5
2.9.2 Voice Receive Mode .................................................................................................................. 2-5
2.9.3 Voice Transmit Mode ................................................................................................................. 2-5
2.9.4 Full-Duplex Receive and Transmit Mode ................................................................................... 2-5
2.9.5 Audio Mode................................................................................................................................ 2-5
2.9.6 Tone Detectors........................................................................................................................... 2-5
2.9.7 Speakerphone Modes................................................................................................................ 2-5
2.10 Full-Duplex Speakerphone (FDSP) Mode (S Model)................................................................................ 2-6
2.11 Caller ID ................................................................................................................................................... 2-6
2.12 Worldwide Country Support ..................................................................................................................... 2-6
2.13 Diagnostics............................................................................................................................................... 2-6
2.13.1 Commanded Tests..................................................................................................................... 2-6
2.13.2 Power On Reset Tests ............................................................................................................... 2-7
2.14 Low Power Sleep Mode............................................................................................................................ 2-7
3 HARDWARE INTERFACE.................................................................................................................................. 3-1
3.1 CX06827 ACF Hardware Pins and Signals .............................................................................................. 3-1
3.1.1 CX06827 ACF Interface Signals ................................................................................................ 3-1
3.2 CX20437 VC Hardware Pins and Signals (S Model).............................................................................. 3-17
3.3 Electrical and Environmental Specifications........................................................................................... 3-23
3.3.1 Operating Conditions, Absolute Maximum Ratings, and Power Requirements ....................... 3-23
3.3.2 Interface and Timing Waveforms .............................................................................................3-24
External Memory Bus Timing .......................................................................................... 3-24
Parallel Host Bus Timing................................................................................................. 3-26
Serial DTE Interface........................................................................................................ 3-28
4 PACKAGE DIMENSIONS................................................................................................................................... 4-1
5 PARALLEL HOST INTERFACE......................................................................................................................... 5-1
5.1 Overview................................................................................................................................................... 5-1
5.2 Register Signal Definitions ....................................................................................................................... 5-3
5.2.1 IER - Interrupt Enable Register (Addr = 1, DLAB = 0) ............................................................... 5-3
5.2.2 FCR - FIFO Control Register (Addr = 2, Write Only) ................................................................. 5-4
5.2.3 IIR - Interrupt Identifier Register (Addr = 2)................................................................................ 5-5
5.2.4 LCR - Line Control Register (Addr = 3)...................................................................................... 5-6
5.2.5 MCR - Modem Control Register (Addr = 4)................................................................................ 5-7
5.2.6 LSR - Line Status Register (Addr = 5) ....................................................................................... 5-8
5.2.7 MSR - Modem Status Register (Addr = 6) ................................................................................. 5-9
5.2.8 RBR - RX Buffer (Receiver Buffer Register) (Addr = 0, DLAB = 0)............................................ 5-9
5.2.9 THR - TX Buffer (Transmitter Holding Register) (Addr = 0, DLAB = 0)...................................... 5-9
5.2.10 Divisor Registers (Addr = 0 and 1, DLAB = 1) ........................................................................... 5-9
5.2.11 SCR - Scratch Register (Addr = 7)............................................................................................. 5-9
5.3 Receiver FIFO Interrupt Operation......................................................................................................... 5-10
5.3.1 Receiver Data Available Interrupt ............................................................................................ 5-10
5.3.2 Receiver Character Timeout Interrupts .................................................................................... 5-10
5.4 Transmitter FIFO Interrupt Operation..................................................................................................... 5-10
5.4.1 Transmitter Empty Interrupt ..................................................................................................... 5-10
SC56D Single Chip ACF Modem Data Sheet
101098C Conexant v
Figures
Figure 1-1. CX06827 ACF Modem Simplified Interface Diagram............................................................................................. 1-2
Figure 1-2. CX06827 ACF Modem Major Interfaces ................................................................................................................ 1-3
Figure 3-1. CX06827 ACF Hardware Signals for Parallel Interface (PARIF = High) ................................................................ 3-2
Figure 3-2. CX06827 ACF 144-Pin TQFP Pin Signals for Parallel Interface (PARIF = High)................................................... 3-3
Figure 3-3. CX06827 ACF Hardware Signals for Serial Interface (PARIF = Low).................................................................... 3-6
Figure 3-4. CX06827 ACF 144-Pin TQFP Pin Signals for Serial Interface (PARIF = Low) ...................................................... 3-7
Figure 3-5. CX20437 VC Hardware Interface Signals............................................................................................................ 3-18
Figure 3-6. CX20437 VC 32-Pin TQFP Pin Signals ............................................................................................................... 3-18
Figure 3-7. Waveforms - External Memory Bus ..................................................................................................................... 3-25
Figure 3-8. Waveforms - Parallel Host Bus ............................................................................................................................ 3-27
Figure 3-9. Waveforms - Serial DTE Interface ....................................................................................................................... 3-28
Figure 4-1. Package Dimensions - 144-Pin TQFP ................................................................................................................... 4-1
Figure 4-2. Package Dimensions - 32-pin TQFP...................................................................................................................... 4-2
Tables
Table 1-1. CX06827 ACF Modem Models and Functions ........................................................................................................ 1-2
Table 2-1. +MS Command Automode Connectivity ................................................................................................................. 2-2
Table 3-1. CX06827 ACF 144-Pin TQFP Pin Signals for Parallel Interface (PARIF = High).................................................... 3-4
Table 3-2. CX06827 ACF 144-Pin TQFP Pin Signals for Serial Interface (PARIF = Low)........................................................ 3-8
Table 3-3. CX06827 ACF Pin Signal Definitions .................................................................................................................... 3-10
Table 3-4. CX06827 ACF I/O Type Definitions....................................................................................................................... 3-16
Table 3-5. CX06827 ACF DC Electrical Characteristics......................................................................................................... 3-16
Table 3-6. CX20437 VC 32-Pin TQFP Pin Signals................................................................................................................. 3-19
Table 3-7. CX20437 VC Pin Signal Definitions ...................................................................................................................... 3-20
Table 3-8. CX20437 VC DC Electrical Characteristics........................................................................................................... 3-22
Table 3-9. CX20437 VC Analog Electrical Characteristics..................................................................................................... 3-22
Table 3-10. Operating Conditions........................................................................................................................................... 3-23
Table 3-11. Absolute Maximum Ratings................................................................................................................................. 3-23
Table 3-12. Current and Power Requirements....................................................................................................................... 3-23
Table 3-13. Timing - External Memory Bus ............................................................................................................................ 3-24
Table 3-14. Timing - Parallel Host Bus................................................................................................................................... 3-26
Table 5-1. Parallel Interface Registers ..................................................................................................................................... 5-2
Table 5-2. Interrupt Sources and Reset Control....................................................................................................................... 5-5
Table 5-3. Programmable Baud Rates ................................................................................................................................... 5-10
SC56D Single Chip ACF Modem Data Sheet
vi Conexant 101098C
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SC56D Single Chip ACF Modem Data Sheet
101098C Conexant 1-1
1 INTRODUCTION
1.1 Overview
The Conexant SC56D Single Chip ACF Modem supports analog data up to 56 kbps, analog fax to 14.4 kbps, telephone
answering machine (TAM)/telephony extensions, voice/speakerphone (optional), and parallel/serial host interface operation
depending on model. Table 1-1 lists the available models. A simplified device interface drawing is shown in Figure 1-1. A
functional interface drawing showing supporting memory is shown in Figure 1-2.
The modem operates with PSTN telephone lines worldwide.
The CX06827 ACF device integrates modem controller (MCU), modem data pump (MDP), bootloader ROM, and analog line
interface codec functions into a single 144-pin TQFP.
The modem operates by executing firmware from external ROM/flash ROM and RAM. Customized modem firmware and
added/modified country profiles can also be executed from external memory, either from ROM/flash ROM or from serial
EEPROM/flash ROM and RAM.
In V.90/K56flex data mode (SC56 models), the modem can receive data at line speeds up to 56 kbps from a digitally
connected V.90 or K56flex-compatible central site modem. In this mode, the modem can transmit data at line speeds up to
V.34 rates.
In V.34 data mode (SC56 and SC33 models), the modem operates at line speeds up to 33.6 kbps. When applicable, error
correction (V.42/MNP 2-4) and data compression (V.42 bis/MNP 5) maximize data transfer integrity and boost average data
throughput. Non-error-correcting mode is also supported.
In V.32 bis data mode, the modem operates at lines speeds up to 14.4 kbps.
In V.22 bis fast connect mode, the modem can connect at 2400 bps with a very short training time, which is very efficient for
small data transfers.
Fax Group 3 send and receive rates are supported up to 14.4 kbps with T.30 protocol.
Downloadable architecture supports downloading of updated/upgraded or customized MCU firmware and MDP code modules
from the host/DTE to the ACF.
V.80 synchronous access mode supports host-controlled communication protocols, e. g., H.324 video conferencing.
In TAM mode, enhanced 2-bit or 4-bit per sample coding schemes at 8 kHz sample rate provide flexible format compatibility
and allows efficient digital storage of voice/audio. Also supported are 8-bit linear and IMA 4-bit ADPCM coding. This mode
supports applications such as digital telephone answering machine (TAM), voice annotation, and recording from and playback
to the telephone line.
The S models, using the optional CX20437 Voice Codec (VC) in a 32-pin TQFP, support position independent, full-duplex
speakerphone (FDSP) operation using microphone and speaker, as well as other voice/TAM applications using handset or
headset.
This data sheet describes the modem capabilities. Commands and parameters are defined in the Commands Reference
Manual (Doc. No. 100500).
SC56D Single Chip ACF Modem Data Sheet
1-2 Conexant 101098C
Table 1-1. CX06827 ACF Modem Models and Functions
Model/Order/Part Numbers Supported Functions
Marketing
Name
Device Set
Order No.
Single Chip
ACF Modem
[144-Pin
TQFP]
Part No.
Voice
Codec (VC)
[32-Pin
TQFP]
Part No.
V.90 and
K56flex Data
V.34 Data V.32 bis Data,
V.17 Fax,
TAM
Voice/FDSP
EMBEDDED APPLICATIONS
SC56D DS56-L147-021 CX06827-11 — Y Y Y —
SC56D/S DS56-L147-031 CX06827-11 20437-11 Y Y Y Y
SC336D DS28-L147-021 CX06827-13 — — Y Y —
SC336D/S DS28-L147-031 CX06827-13 20437-11 — Y Y Y
SC144D DS96-L147-021 CX06827-14 — — — Y —
SC144D/S DS96-L147-031 CX06827-14 20437-11 — — Y Y
AFTERMARKET APPLICATIONS
SC56D DS56-L144-301 CX06827-11 — Y Y Y —
SC56D/S DS56-L144-311 CX06827-11 20437-11 Y Y Y Y
Notes:
1. Model options:
S Voice/full-duplex speakerphone (FDSP) and analog cellular
56 56 kbps max. rate per V.90
33 33.6 kbps max. rate per V.34
14 14.4 kbps max. rate per V.32 bis.
2. Supported functions (Y = Supported; — = Not supported):
TAM Telephone answering machine (Voice playback and record through telephone line)
FDSP Full-duplex speakerphone and voice playback and record through telephone line, handset, and mic/speaker.
3. For ordering purposes, the CX prefix may not be included in the part number for some devices. Also, the CX prefix may not appear in the part number as branded on
some devices.
CX06827
Single Chip Modem
144-Pin TQFP CX20437
Voice Codec
(VC)
32-Pin TQFP
(Optional)
MIC
SPEAKER
TIP
RING
Telephone
Line
Interface
Discrete
Components
101098_F1-1_SID
TIP
RING HANDSET (OPTIONAL)
TELEPHONE LINE
(OPTIONAL)
PARALLEL
HOST BUS OR
SERIAL DTE
INTERFACE
Figure 1-1. CX06827 ACF Modem Simplified Interface Diagram
SC56D Single Chip ACF Modem Data Sheet
101098C Conexant 1-3
CX06827
Single Chip ACF Modem
144-Pin TQFP
CX20437
Voice Codec (VC)
32-Pin TQFP
(Optional)
Line Interface
Codec
Modem Data
Pump (MDP)
Digital Speaker
Circuit (Optional)
Parallel Host
or Serial DTE
Interface
MIC
SPEAKER
101098_F1-2_FID
SOUNDUCER
HS Hybrid
Components
(Optional)
RAM
1M (128K x 8)
Flash ROM
2M (256K x 8)
Microcontroller
Unit (MCU)
Serial EEPROM
2K (256 x 8) to
256K (32K x 8)
(Optional)
TIP
RING
Telephone
Line Interface
Discrete
Components
TIP
RING
Voice Relay,
HS Pickup
Detector
(Optional)
TELEPHONE
LINE
TELEPHONE
HANDSET
DAA Hardware
(Mic/Speaker)
Interface
(Optional)
Bootloader
ROM
Figure 1-2. CX06827 ACF Modem Major Interfaces
SC56D Single Chip ACF Modem Data Sheet
1-4 Conexant 101098C
1.2 Features
1.2.1 General Modem Features
• Data modem
− ITU-T V.90/K56flex (SC56 models)/V.34 (SC56 and SC33 models), V.32bis, V.32, V.22 bis, V.22, V.23, and V.21;
Bell 212A and Bell 103
− V.42 LAPM and MNP 2-4 error correction
− V.42 bis and MNP 5 data compression
− MNP 10EC™ enhanced cellular performance
− V.250 and V.251 commands
• V.22 bis fast connect
• Fax modem send and receive rates up to 14.4 kbps
− V.17, V.29, V.27 ter, and V.21 channel 2
− EIA/TIA 578 Class 1 and T.31 Class 1.0, and EIA/TIA 578 Class 2 commands
• V.80 synchronous access mode supports host-controlled communication protocols with H.324 interface support
• Interfaces to external ROM/flash ROM, RAM, and optional serial EEPROM
• Downloadable Architecture
− Downloadable MCU firmware from the host/DTE to flash ROM
− Downloadable MDP code modules from the MCU transparent to the host
• Data/Fax/Voice call discrimination
• Hardware-based modem controller and digital signal processor (DSP)
• Worldwide operation
− Complies to TBR21 and other country requirements
− Caller ID detection
− Call progress, blacklisting
− External ROM/flash ROM includes default values for 29 countries
• Caller ID and distinctive ring detect
• Telephony/TAM
− V.253 commands
− 2-bit and 4-bit Conexant ADPCM, 8-bit linear PCM, and 4-bit IMA coding
− 8 kHz sample rate
− Concurrent DTMF, ring, and Caller ID detection
• Full-duplex speakerphone (FDSP) mode using optional CX20437 Voice Codec (S models)
− Microphone and speaker interface
− Telephone handset or headset interface
− Acoustic and line echo cancellation
− Microphone gain and muting
− Speaker volume control and muting
• Built-in host/DTE interface with speeds up to 230.4 kbps
− Parallel 16550A UART-compatible interface
− Serial ITU-T V.24 (EIA/TIA-232-E) logical interface
• Direct mode (serial DTE interface)
• Flow control and speed buffering
• Automatic format/speed sensing
• Serial async/sync data; parallel async data
• Thin packages support low profile designs (1.6 mm max. height)
− CX06827 ACF: 144-pin TQFP
− CX20437 VC: 32-pin TQFP
• +3.3V operation with +5V tolerant digital inputs
• Typical power use
SCFACF: 274 mW (Normal Mode); 27.7 mW (Sleep Mode)
VC: 5 mW (Normal Mode)
1.2.2 Applications
• Desktop Modems
• Serial box modems
• Remote monitoring and data collection systems
• Standalone TAM/fax machines
SC56D Single Chip ACF Modem Data Sheet
101098C Conexant 1-5
1.3 Technical Overview
1.3.1 General Description
Modem operation, including dialing, call progress, telephone line interface, telephone handset interface, optional
voice/speakerphone interface, and host interface functions are supported and controlled through the V.250, V.251, and
V.253-compatible command set.
The modem hardware connects to the host via a parallel or serial interface as selected by the PARIF input. The OEM adds a
crystal circuit, ROM/flash ROM, RAM, telephone line interface, telephone handset/telephony extension interface,
voice/speakerphone interface, optional external serial EEPROM, and other supporting discrete components as supported by
the modem model (Table 1-1) and required by the application to complete the system.
Customized modem firmware and additional or modified country profiles can be supported by the use external flash ROM
(optional serial EEPROM can also be used if external flash ROM capacity is exceeded). Customized code can include OEM-
defined commands, i.e., identification codes (I3), identifier string (I4), manufacturer identification (+GMI), model identification
(+GMM), and revision identification (+GMR), as well as code modification.
Parallel interface operation is selected by PARIF input high.
Serial interface operation is selected by PARIF input low.
1.3.2 MCU Firmware
MCU firmware performs processing of general modem control, command sets, data modem, error correction and data
compression (ECC), fax class 1, fax class 1.0, fax class 2, voice/audio/TAM/speakerphone, worldwide, V.80, and serial
DTE/parallel host interface functions according to modem models.
MCU firmware can be customized to include OEM-defined commands, i.e., identification codes (I3), identifier string (I4),
manufacturer identification (+GMI), model identification (+GMM), and revision identification (+GMR), as well as code
modification.
The modem firmware is provided in object code form for the OEM to program into external ROM/flash ROM. The modem
firmware may also be provided in source code form under a source code addendum license agreement.
1.3.3 Operating Modes
Data/Fax Modes
In V.90/K56flex data modem mode (SC56 models), the modem can receive data from a digital source using a V.90- or
K56flex-compatible central site modem at line speeds up to 56 kbps. Asymmetrical data transmission supports sending data
at line speeds up to V.34 rates. This mode can fallback to full-duplex V.34 mode and to lower rates as dictated by line
conditions.
In V.34 data modem mode (SC56 and SC33 models), the modem can operate in 2-wire, full-duplex, asynchronous modes at
line rates up to 33.6 kbps. Data modem modes perform complete handshake and data rate negotiations. Using V.34
modulation to optimize modem configuration for line conditions, the modem can connect at the highest data rate that the
channel can support from 33600 bps down to 2400 bps with automatic fallback. Automode operation in V.34 is provided in
accordance with PN3320 and in V.32 bis in accordance with PN2330. All tone and pattern detection functions required by the
applicable ITU or Bell standards are supported.
In V.32 bis data modem mode, the modem can operate at line speeds up to 14.4 kbps.
In V.22 bis fast connect data mode, the modem can connect at 2400 bps with a very short training time, which is very efficient
for small data transfers.
In fax modem mode, the modem can operate in 2-wire, half-duplex, synchronous modes and can support Group 3 facsimile
send and receive speeds of 14400, 12000, 9600, 7200, 4800, and 2400 bps. Fax data transmission and reception performed
by the modem are controlled and monitored through the EIA/TIA-578 Fax Class 1, T.31 Fax Class 1.0, or Fax Class 2
command interface. Full HDLC formatting, zero insertion/deletion, and CRC generation/checking are provided.
Synchronous Access Mode (SAM) - Video Conferencing
V.80 Synchronous Access Mode between the modem and the host/DTE is provided for host-controlled communication
protocols, e.g., H.324 video conferencing applications.
Voice-call-first (VCF) before switching to a videophone call is also supported.
SC56D Single Chip ACF Modem Data Sheet
1-6 Conexant 101098C
Worldwide Operation
The modem operates in TBR21-compliant and other countries. Country-dependent modem parameters for functions such as
dialing, carrier transmit level, calling tone, call progress tone detection, answer tone detection, blacklisting, caller ID, and relay
control are programmable (see Section 2.12).
Country code IDs are defined by ITU-T T.35.
External ROM/flash ROM includes default profiles for 29 countries including TBR21-compliant profiles. These profiles can be
overridden by modified values stored in external serial EEPROM. A maximum of 31 country profiles can be stored in external
ROM/flash ROM. Additional country profiles can be stored in external serial EEPROM (request additional country profiles from
a Conexant Sales Office). The default countries supported are:
Country Country Code Country Country Code Country Country Code
Australia 09 India 53 Portugal 8B
Austria 0A Ireland 57 Singapore 9C
Belgium 0F Italy 59 South Africa 9F
Brazil 16 Japan 00 Spain A0
China 26 Korea 61 Sweden A5
Denmark 31 Malaysia 6C Switzerland A6
Finland 3C Mexico 73 Taiwan FE
France 3D Netherlands 7B United Kingdom B4
Germany 42 Norway 82 United States B5
Greece 46 Poland 8A
TAM Mode
TAM Mode features include 8-bit linear coding at 8 kHz sample rate. Tone detection/ generation, call discrimination, and
concurrent DTMF detection are also supported. ADPCM (4-bit IMA) coding is also supported to meet Microsoft WHQL logo
requirements.
TAM Mode is supported by four submodes:
1. Online Voice Command Mode supports connection to the telephone line or, for S models, a
microphone/speaker/handset/headset.
2. Voice Receive Mode supports recording voice or audio data input from the telephone line or, for S models, a
microphone/handset/headset.
3. Voice Transmit Mode supports playback of voice or audio data to the telephone line or, for S models, a
speaker/handset/headset.
4. Full-duplex Receive and Transmit Mode.
Voice/Speakerphone Mode (S Models)
The S models include additional telephone handset, external microphone, and external speaker interfaces which support
voice and full-duplex speakerphone (FDSP) operation.
Hands-free full-duplex telephone operation is supported in Speakerphone Mode under host control. Speakerphone Mode
features an advanced proprietary speakerphone algorithm which supports full-duplex voice conversation with acoustic, line,
and handset echo cancellation. Parameters are constantly adjusted to maintain stability with automatic fallback from full-
duplex to pseudo-duplex operation. The speakerphone algorithm allows position independent placement of microphone and
speaker. The host can separately control volume, muting, and AGC in microphone and speaker channels.
1.3.4 Reference Design
A data/fax/TAM/speakerphone reference design for an external modem (RD00-D930) is available to minimize application
design time, reduce development cost, and accelerate market entry.
A design package is available in electronic form. This package includes schematics, bill of materials (BOM), vendor part list
(VPL), board layout files in Gerber format, and complete documentation.
SC56D Single Chip ACF Modem Data Sheet
101098C Conexant 1-7
1.4 Hardware Description
1.4.1 CX06827 Modem Controller and DSP
The CX06827 Modem Controller and DSP (ACF), packaged in a 144-pin TQFP, includes a Microcontroller (MCU), a Modem
Data Pump (MDP), bootloader ROM, and line interface functions.
The ACF connects to host via a parallel host (PARIF = high) or a logical V.24 (EIA/TIA-232-E) serial DTE interface (PARIF =
low).
The ACF performs the command processing and host interface functions. The crystal frequency is 28.224 MHz.
The ACF connects to external OEM-supplied ROM/flash ROM and RAM over a non-multiplexed 19-bit address bus and 8-bit
data bus.
The ACF optionally connects to an external OEM-supplied serial EEPROM over a dedicated 2-line serial interface. The
capacity of the EEPROM can be 256 bytes up to 32k bytes. The EEPROM can hold information such as firmware
configuration customization and country code parameters.
The ACF performs telephone line signal modulation/demodulation in a hardware digital signal processor (DSP) which reduces
computational load on the host processor.
1.4.2 CX20437 Voice Codec
The optional CX20437 Voice Codec (VC), packaged in a 32-pin TQFP, supports voice/full-duplex speakerphone (FDSP)
operation with interfaces to a microphone and speaker and to a telephone handset/headset.
1.5 Commands
The modem supports data modem, fax class 1 modem, fax class 1.0 modem, fax class 2 modem, voice/audio, full-duplex
speakerphone (FDSP), MNP 10/MNP 10EC, and V.80 commands, and S Registers in accordance with modem model
options. See Doc. No. 100722 for a description of the commands.
Data Modem Operation. Data modem functions operate in response to the AT commands when +FCLASS=0. Default
parameters support U.S./Canada operation.
MNP 10 Operation. MNP 10 functions operate in response to MNP 10 commands.
MNP 10EC Operation. MNP 10EC is enabled by the -SEC=1 command.
Fax Modem Operation. Facsimile functions operate in response to fax class 1 commands when +FCLASS=1, fax class 1.0
commands when +FCLASS=1.0, or to fax class 2 commands when +FCLASS=2 is installed.
Voice/Audio Operation. Voice/audio mode functions operate in response to voice/audio commands when +FCLASS=8.
Speakerphone Operation. FDSP functions operate in response to speakerphone commands when +FCLASS=8 and
+VSP=1 is selected.
SC56D Single Chip ACF Modem Data Sheet
1-8 Conexant 101098C
This page is intentionally blank.
SC56D Single Chip ACF Modem Data Sheet
101098C Conexant 2-1
2 TECHNICAL SPECIFICATIONS
2.1 Serial DTE Interface Operation
2.1.1 Automatic Speed/Format Sensing
Command Mode and Data Modem Mode. The modem can automatically determine the speed and format of the data sent
from the DTE. The modem can sense speeds of 300, 600, 1200, 2400, 4800, 7200, 9600, 12000, 14400, 16800, 19200,
21600, 24000, 26400, 28800, 38400, 57600, 115200, and 230400 bps and the following data formats:
Parity
Data Length
(No. of Bits)
No. of
Stop Bits
Character Length
(No. of Bits)
None 7 2 10
Odd 7 1 10
Even 7 1 10
None 8 1 10
Odd 8 1 11*
Even 8 1 11*
*11-bit characters are sensed, but the parity bits are stripped off
during data transmission in Normal and Error Correction modes.
The modem can speed sense data with mark or space parity and configures itself as follows:
DTE Configuration Modem Configuration
7 mark 7 none
7 space 8 none
8 mark 8 none
8 space 8 even
Fax Modem Mode. In V.17 fax mode, the modem can sense speeds up to 230.4 kbps.
2.2 Parallel Host Bus Interface Operation
Command Mode and Data Modem Mode. The modem can operate at rates up to 230.4 kbps by programming the Divisor
Latch in the parallel interface registers if supported by communications software and/or driver (a Windows 95/98 driver is
available from Conexant).
Fax Modem Mode. In V.17 mode, the modem can operate at rates up to 230.4 kbps by programming the Divisor Latch in the
parallel interface registers if supported by communications software and/or driver (a Windows 95/98 driver is available from
Conexant).
2.3 Establishing Data Modem Connections
Telephone Number Directory
The modem supports four telephone number entries in a directory that can be saved in a serial NVRAM. Each telephone
number can be up to 32 characters (including the command line terminating carriage return) in length. A telephone number
can be saved using the &Zn=x command, and a saved telephone number can be dialed using the DS=n command.
Dialing
DTMF Dialing. DTMF dialing using DTMF tone pairs is supported in accordance with ITU-T Q.23. The transmit tone level
complies with Bell Publication 47001.
Pulse Dialing. Pulse dialing is supported in accordance with EIA/TIA-496-A.
Blind Dialing. The modem can blind dial in the absence of a dial tone if enabled by the X0, X1, or X3 command.
SC56D Single Chip ACF Modem Data Sheet
2-2 Conexant 101098C
Modem Handshaking Protocol
If a tone is not detected within the time specified in the S7 register after the last digit is dialed, the modem aborts the call
attempt.
Call Progress Tone Detection
Ringback, equipment busy, congested tone, warble tone, and progress tones can be detected in accordance with the
applicable standard.
Answer Tone Detection
Answer tone can be detected over the frequency range of 2100 ± 40 Hz in ITU-T modes and 2225 ± 40 Hz in Bell modes.
Ring Detection
A ring signal can be detected from a TTL-compatible 15.3 Hz to 68 Hz square wave input.
Billing Protection
When the modem goes off-hook to answer an incoming call, both transmission and reception of data are prevented for 2
seconds (data modem) or 4 seconds (fax adaptive answer) to allow transmission of the billing tone signal.
Connection Speeds
The modem functions as a data modem when the +FCLASS=0 command is active.
Line connection can be selected using the +MS command. The +MS command selects modulation, enables/disables
automode, and selects minimum and maximum line speeds (Table 2-1).
Automode
Automode detection can be enabled by the +MS command to allow the modem to connect to a remote modem in accordance
with draft PN-3320 for V.34 (Table 2-1).
Table 2-1. +MS Command Automode Connectivity
<mod> Modulation Possible Rates (bps) 1Notes
V21 V.21 300
V22 V.22 1200
V22B V.22 bis 2400 or 1200
V23 V.23 1200 See Note 2
V32 V.32 9600 or 4800
V32B V.32 bis 14400, 12000, 9600, 7200, or 4800 Default for SC14
models
V34 V.34 33600, 31200, 28800, 26400, 24000, 21600, 19200, 16800,
14400, 12000, 9600, 7200, 4800, or 2400
Default for SC33
models
V90 V.90 56000, 54667, 53333, 52000, 50667, 49333, 48000, 46667,
45333, 42667, 41333, 40000, 38667, 37333, 36000, 34667,
33333, 32000, 30667, 29333, 28000
Default for SC56
models
K56 K56flex 56000, 54000, 52000, 50000, 48000, 46000, 44000, 42000,
40000, 38000, 36000, 34000, 32000
B103 Bell 103 300
B212 Bell 212 1200
Notes:
1. See optional <automode>, <min_rate>, and <max_rate> subparameters for the +MS command.
2. For V.23, originating modes transmit at 75 bps and receive at 1200 bps; answering modes transmit at 1200 bps and
receive at 75 bps. The rate is always specified as 1200 bps. V.23 half duplex is not supported.
3. If the DTE speed is set to less than the maximum supported DCE speed in automode, the maximum connection speed is
limited to the DTE speed.
SC56D Single Chip ACF Modem Data Sheet
101098C Conexant 2-3
2.4 Data Mode
Data mode exists when a telephone line connection has been established between modems and all handshaking has been
completed.
Speed Buffering (Normal Mode)
Speed buffering allows a DTE to send data to, and receive data from, a modem at a speed different than the line speed. The
modem supports speed buffering at all line speeds.
Flow Control
DTE-to-Modem Flow Control. If the modem-to-line speed is less than the DTE-to-modem speed, the modem supports
XOFF/XON or RTS/CTS flow control with the DTE to ensure data integrity.
Escape Sequence Detection
The +++ escape sequence can be used to return control to the command mode from the data mode. Escape sequence
detection is disabled by an S2 Register value greater than 127.
BREAK Detection
The modem can detect a BREAK signal from either the DTE or the remote modem. The \Kn command determines the
modem response to a received BREAK signal.
Telephone Line Monitoring
GSTN Cleardown (V.90, K56flex, V.34, V.32 bis, V.32). Upon receiving GSTN Cleardown from the remote modem in a non-
error correcting mode, the modem cleanly terminates the call.
Loss of Carrier (V.22 bis and Below). If carrier is lost for a time greater than specified by the S10 register, the modem
disconnects (except MNP 10).
Receive Space Disconnect (V.22 bis and Below). If selected by the Y1 command in non-error-correction mode, the modem
disconnects after receiving 1.6 ± 10% seconds of continuous SPACE.
Send SPACE on Disconnect (V.22 bis and Below)
If selected by the Y1 command in non-error-correction mode, the modem sends 4 ± 10% seconds of continuous SPACE
when a locally commanded hang-up is issued by the &Dn or H command.
Fall Forward/Fallback (V.90/K56flex/V.34/V.32 bis/V.32)
During initial handshake, the modem will fallback to the optimal line connection within V.90/K56flex/V.34/V.32 bis/V.32 mode
depending upon signal quality if automode is enabled by the +MS or N1 command.
When connected in V.90/K56flex/V.34/V.32 bis/V.32 mode, the modem will fall forward or fallback to the optimal line speed
within the current modulation depending upon signal quality if fall forward/fallback is enabled by the %E2 command.
Retrain
The modem may lose synchronization with the received line signal under poor or changing line conditions. If this occurs,
retraining may be initiated to attempt recovery depending on the type of connection.
The modem initiates a retrain if line quality becomes unacceptable if enabled by the %E command. The modem continues to
retrain until an acceptable connection is achieved, or until 30 seconds elapse resulting in line disconnect.
Programmable Inactivity Timer
The modem disconnects from the line if data is not sent or received for a specified length of time. In normal or error-correction
mode, this inactivity timer is reset when data is received from either the DTE or from the line. This timer can be set to a value
between 0 and 255 seconds by using register S30. A value of 0 disables the inactivity timer.
SC56D Single Chip ACF Modem Data Sheet
2-4 Conexant 101098C
DTE Signal Monitoring (Serial DTE Interface Only)
DTR#. When DTR# is asserted, the modem responds in accordance with the &Dn and &Qn commands.
RTS#. RTS# is used for flow control if enabled by the &K command in normal or error-correction mode.
2.5 Error Correction and Data Compression
V.42 Error Correction
V.42 supports two methods of error correction: LAPM and, as a fallback, MNP 4. The modem provides a detection and
negotiation technique for determining and establishing the best method of error correction between two modems.
MNP 2-4 Error Correction
MNP 2-4 is a data link protocol that uses error correction algorithms to ensure data integrity. Supporting stream mode, the
modem sends data frames in varying lengths depending on the amount of time between characters coming from the DTE.
V.42 bis Data Compression
V.42 bis data compression mode, enabled by the %Cn command or S46 register, operates when a LAPM or MNP 10
connection is established.
The V.42 bis data compression employs a “string learning” algorithm in which a string of characters from the DTE is encoded
as a fixed length codeword. Two 2k-byte dictionaries are used to store the strings. These dictionaries are dynamically
updated during normal operation.
MNP 5 Data Compression
MNP 5 data compression mode, enabled by the %Cn command, operates during an MNP connection.
In MNP 5, the modem increases its throughput by compressing data into tokens before transmitting it to the remote modem,
and by decompressing encoded received data before sending it to the DTE.
2.6 MNP 10 Data Throughput Enhancement
MNP 10 protocol and MNP Extended Services enhance performance under adverse channel conditions such as those found
in rural, long distance, or cellular environments. An MNP 10 connection is established when an MNP 2-4 connection is
negotiated with a remote modem supporting MNP 10.
MNP Extended Services. The modem can quickly switch to MNP 10 operation when the remote modem supports MNP 10
and both modems are configured to operate in V.42.
V.42 bis/MNP 5 Support. V.42 bis/MNP 10 can operate with V.42 bis or MNP 5 data compression.
2.7 MNP 10EC™ Enhanced Cellular Connection
A traditional landline modem, when used for high-speed cellular data transmission, typically encounters frequent signal
interference and degradation in the connection due to the characteristics of the analog cellular network. In this case, cellular-
specific network impairments, such as non-linear distortion, fading, hand-offs, and high signal-to-noise ratio, contribute to an
unreliable connection and lower data transfer performance. Implementations relying solely on protocol layer methods, such as
MNP 10, generally cannot compensate for the landline modem's degraded cellular channel performance.
The modem achieves higher cellular performance by implementing enhanced cellular connection techniques at both the
physical and protocol layers, depending on modem model. The modem enhances the physical layer within the modulation by
optimizing its responses to sudden changes in the cellular connection. The MNP 10EC protocol layer implemented in the
modem firmware improves data error identification/correction and maximizes data throughput by dynamically adjusting speed
and packet size based on signal quality and data error performance.
SC56D Single Chip ACF Modem Data Sheet
101098C Conexant 2-5
2.8 Fax Class 1, Fax Class 1.0, and Fax Class 2 Operation
Facsimile functions operate in response to fax class 1 commands when +FCLASS=1, fax class 1.0 commands when
+FCLASS=1.0, or to fax class 2 commands when +FCLASS=2 is installed
In the fax mode, the on-line behavior of the modem is different from the data (non-fax) mode. After dialing, modem operation
is controlled by fax commands. Some AT commands are still valid but may operate differently than in data modem mode.
Calling tone is generated in accordance with T.30.
2.9 Voice/Audio Mode
Voice and audio functions are supported by the Voice Mode. Voice Mode includes three submodes: Online Voice Command
Mode, Voice Receive Mode, and Voice Transmit Mode.
2.9.1 Online Voice Command Mode
This mode results from the connection to the telephone line or a voice/audio I/O device (e.g., microphone, speaker, or
handset) through the use of the +FCLASS=8 and +VLS commands. After mode entry, AT commands can be entered without
aborting the connection.
2.9.2 Voice Receive Mode
This mode is entered when the +VRX command is active in order to record voice or audio data input at the RIN pin, typically
from a microphone/handset or the telephone line.
Received analog voice samples are converted to digital form and compressed for reading by the host. AT commands control
the codec bits-per-sample rate.
Received analog mono audio samples are converted to digital form and formatted into 8-bit unsigned linear PCM format for
reading by the host. AT commands control the bit length and sampling rate. Concurrent DTMF/tone detection is available at
the 8 kHz sample rate.
2.9.3 Voice Transmit Mode
This mode is entered when the +VTX command is active in order to playback voice or audio data to the TXA output, typically
to a speaker/handset or to the telephone line.
Digitized voice data is decompressed and converted to analog form at the original compression quantization sample-per-bits
rate then output to the TXA output.
Digitized audio data is converted to analog form then output to the TXA output.
2.9.4 Full-Duplex Receive and Transmit Mode
This mode is entered when the +VTR command is active in order to concurrently receive and transmit voice.
2.9.5 Audio Mode
The audio mode enables the host to transmit and receive 8-bit audio signals. In this mode, the modem directly accesses the
internal analog-to-digital (A/D) converter (ADC) and the digital-to-analog (D/A) converter (DAC). Incoming analog audio
signals can then be converted to digital format and digital signals can be converted to analog audio output.
2.9.6 Tone Detectors
The tone detector signal path is separate from the main received signal path thus enabling tone detection to be independent
of the configuration status. In Tone Mode, all three tone detectors are operational.
2.9.7 Speakerphone Modes
Speakerphone modes are controlled in voice mode with the following commands:
Use Speakerphone After Dialing or Answering (+VSP=1). +VSP=1 selects speakerphone mode while in +FCLASS=8
mode. Speakerphone operation is entered during Voice Online Command mode after completing dialing or answering.
Speakerphone Settings. The +VGM and +VGS commands can be used to control the microphone gain and speaker volume,
respectively. The VGM and +VGS commands are valid only after the modem has entered the Voice Online mode while in the
+VSP=1 setting.
SC56D Single Chip ACF Modem Data Sheet
2-6 Conexant 101098C
2.10 Full-Duplex Speakerphone (FDSP) Mode (S Model)
The modem operates in FDSP mode when +FCLASS=8 and +VSP=1 (see Section 2.9.7).
In FDSP Mode, speech from a microphone or handset is converted to digital form, shaped, and output to the telephone line
through the line interface circuit. Speech received from the telephone line is shaped, converted to analog form, and output to
the speaker or handset. Shaping includes both acoustic and line echo cancellation.
2.11 Caller ID
Caller ID can be enabled/disabled using the +VCID command. When enabled, caller ID information (date, time, caller code,
and name) can be passed to the DTE in formatted or unformatted form. Inquiry support allows the current caller ID mode and
mode capabilities of the modem to be retrieved from the modem.
2.12 Worldwide Country Support
Internal modem firmware supports 29 country profiles (see Section 1.3.2). These country profiles include the following
country-dependent parameters:
• Dial tone detection levels and frequency ranges.
• DTMF dialing parameters: Transmit output level, DTMF signal duration, and DTMF interdigit interval.
• Pulse dialing parameters: Make/break times, set/clear times, and dial codes are programmable
• Ring detection frequency range.
• Blind dialing enabled/disable.
• Carrier transmit level (through S91 for data and S92 for fax). The maximum, minimum, and default values can be defined
to match specific country and DAA requirements.
• Calling tone is generated in accordance with V.25. Calling tone may be toggled (enabled/disabled) by inclusion of a “^”
character in a dial string. It may also be disabled.
• Frequency and cadence of tones for busy, ringback, congested, warble, dial tone 1, and dial tone 2.
• Answer tone detection period.
• Blacklist parameters. The modem can operate in accordance with requirements of individual countries to prevent misuse
of the network by limiting repeated calls to the same number when previous call attempts have failed. Call failure can be
detected for reasons such as no dial tone, number busy, no answer, no ringback detected, voice (rather than modem)
detected, and key abort (dial attempt aborted by user). Actions resulting from such failures can include specification of
minimum inter-call delay, extended delay between calls, and maximum numbers of retries before the number is
permanently forbidden ("blacklisted").
These country profiles may be altered or customized by modifying the country-dependent parameters. Additional profiles may
also be included. There are two ways to add or modify profiles:
• Incorporating additional or modified profiles into external flash ROM containing the entire modem firmware code.
• Linking additional or modified profiles from an external serial EEPROM (needed only if the external flash ROM capacity is
exceeded.
Please contact an FAE at the local Conexant sales office if a country code customization is required.
2.13 Diagnostics
2.13.1 Commanded Tests
Diagnostics are performed in response to &T commands.
Analog Loopback (&T1 Command). Data from the local DTE is sent to the modem, which loops the data back to the local
DTE.
SC56D Single Chip ACF Modem Data Sheet
101098C Conexant 2-7
2.13.2 Power On Reset Tests
Upon power on, the modem performs tests of the modem, internal and external RAM, and NVRAM. If the modem, internal
RAM, or external RAM test fails, the TMIND# output is pulsed (serial interface version) or the DCD bit in the parallel interface
register is pulsed (parallel interface version) as follows:
Internal or external RAM test fails: One pulse cycle (pulse cycle = 0.5 sec. on, 0.5 sec. off) every 1.5 seconds.
Modem device test fails: Three pulse cycles every 1.5 seconds.
If the NVRAM test fails (due to NVRAM failure or if NVRAM is not installed), the test failure is reported by AT commands that
normally use the NVRAM, e.g., the &V command.
2.14 Low Power Sleep Mode
Sleep Mode Entry. The modem enters the low power sleep mode when no line connection exists and no host activity occurs
for the period of time specified in the S24 register. All modem circuits are turned off except the internal clock circuitry in order
to consume reduced power while being able to immediately wake up and resume normal operation.
Wake-up. Wake-up occurs when a ring is detected on the telephone line, the host writes to the modem (parallel interface), or
the DTE sends a character to the modem (serial interface).
SC56D Single Chip ACF Modem Data Sheet
2-8 Conexant 101098C
This page is intentionally blank.
SC56D Single Chip ACF Modem Data Sheet
101098C Conexant 3-1
3 HARDWARE INTERFACE
3.1 CX06827 ACF Hardware Pins and Signals
3.1.1 CX06827 ACF Interface Signals
ACF hardware interface signals for parallel interface are shown by major interface in Figure 3-1, are shown by pin number in
Figure 3-2, and are listed by pin number in Table 3-1.
ACF hardware interface signals for serial interface are shown by major interface in Figure 3-3, are shown by pin number in
Figure 3-4, and are listed by pin number in Table 3-2.
The ACF hardware interface signals are defined in Table 3-3.
ACF I/O types are defined in Table 3-4.
ACF DC electrical characteristics are listed in Table 3-5.
SC56D Single Chip ACF Modem Data Sheet
3-2 Conexant 101098C
XTLI
XTLO
CLKIN
CLKOUT
NMIP
PARIF (MK0)
NOXYCK
HCS# (PD4)
HRD# (PD6)
HWT# (PD5)
HINT (PB7)
HA0 (PD0)
HA1 (PD1)
HA2 (PD2)
HD0 (PC0)
HD1 (PC1)
HD2 (PC2)
HD3 (PC3)
HD4 (PC4)
HD5 (PC5)
HD6 (PC6)
HD7 (PC7)
RES1#
RES2#
LPO
PD3
PE5
PE7
XXCLK
BD2CLK
DV1TP
PHS2
TESTP
P_PA00
PA1
PA3
PA4
PA5
PB1
PB6
PD7
PE1
PE2
PE6
P_GP01
P_PA03
P_PA07
PA2
PA6
VGG
VDD
VDD
VDD
VDD
VDD
VDD
VDD
VDD
VDD
VDD
DVDD
DVDD
AVDD
VSS
VSS
VSS
VSS
DVSS
AGND
AGND
AGND
116
117
115
67
119
16
54
21
23
22
112
17
18
19
123
124
126
127
128
130
132
133
41
142
63
20
30
32
55
65
114
122
113
61
34
36
37
38
104
110
53
25
26
31
58
60
57
35
39
66
29
48
64
84
103
111
125
131
59
118
1
10
135
46
71
106
129
11
9
15
134
PARALLEL HOST
INTERFACE
NVMCLK (PA7)
NVMDATA (PE3)
OH# (PE0)
LCS (PE4)
RING (PA0)
LINE_OUT_P
LINE_OUT_M
LINE_IN
ASPKR
MIC_IN
MIC_BIAS
M_RELAY_A
M_ACT_90
DLPBK_BAR
VREF
VC
SLEEP_IN
MCLKIN
CNTLSIN
RXOUT
TXSIN
STROBE
SCLK
IA1CLK (P_PX03)
SA1CLK (P_PX02)
SR4OUT (P_PX00)
SR4IN
SR1IO (P_PX07)
IASLEEP (P_PF05)
MCLKOUT (P_PB00)
SR2CLK (P_PGP05)
SA2CLK (P_PX05)
SR3OUT
SR3IN (P_PX01)
SR2IO (P_PX06)
PLLVDD
PLLGND
A00
A01
A02
A03
A04
A05
A06
A07
A08
A09
A10
A11
A12
A13
A14
A15
A16 (PB0)
A17 (PB4)
A18 (PB5)
D0
D1
D2
D3
D4
D5
D6
D7
RD#
WT#
RAMSEL# (PB3)
ROMSEL# (PB2)
RESERVED
RESERVED
RESERVED
RESERVED
RESERVED
40
27
24
28
33
137
138
143
136
141
144
8
12
13
139
140
14
3
2
6
4
7
5
51
50
49
52
62
56
44
96
45
42
43
47
88
89
77
78
79
80
81
82
83
85
86
87
90
91
92
93
94
95
102
108
109
68
69
70
72
73
74
75
76
121
120
107
105
97
98
99
100
101
101098_F3-1_HI_CX06827 144T PAR
+3.3V
CX06827
SINGLE CHIP
ACF MODEM
144-PIN TQFP
PARALLEL
INTERFACE
(PARIF = HIGH)
1uF
CRYSTAL
CIRCUIT
EXTERNAL
RAM AND ROM
DAA
+3.3V OR +5V
CX20437
VOICE CODEC
(VC)
(OPTIONAL)
+3.3V
NC
NC
+3.3V
NC
240K
47K
47K
47K
SCL
SDA
+3.3V
EEPROM (OPTIONAL)
OH#
LCS
RING
TXAP
TXAM
RXA
NC
0.1
AGND
10
SPEAKER CIRCUIT
+3.3V
+3.3V
+3.3V
33
33
33
SLEEP
M_CLKIN
M_SCK
M_STROBE
M_TXSIN
M_RXOUT
M_CNTRLSIN
NC
+3.3V A (FILTERED)
NC
NC
(PARALLEL HOST
INTERFACE ONLY)
NC
0.1
AGND
10
Figure 3-1. CX06827 ACF Hardware Signals for Parallel Interface (PARIF = High)
SC56D Single Chip ACF Modem Data Sheet
101098C Conexant 3-3
101098 F3-2 PO CX06827 144T Par
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
108
107
106
105
104
103
102
101
100
99
98
97
96
95
94
93
92
91
90
89
88
87
86
85
84
83
82
81
80
79
78
77
76
75
74
73
144
143
142
141
140
139
138
137
136
135
134
133
132
131
130
129
128
127
126
125
124
123
122
121
120
119
118
117
116
115
114
113
112
111
110
109
DVDD
CNTLSIN
MCLKIN
TXSIN
SCLK
RXOUT
STROBE
M_RELAY_A
AGND
DVDD
DVSS
M_ACT_90
DLPBK_BAR
SLEEP_IN
AGND
PARIF (MK0)
HA0 (PD0)
HA1 (PD1)
HA2 (PD2)
PD3
HCS# (PD4)
HWT# (PD5)
HRD# (PD6)
OH# (PE0)
PE1
PE2
NVMDATA (PE3)
LCS (PE4)
VDD
PE5
PE6
PE7
RING (PA0)
PA1
PA2
PA3
A17 (PB4)
RAMSEL# (PB3)
VSS
ROMSEL# (PB2)
PB1
VDD
A16 (PB0)
RESERVED
RESERVED
RESERVED
RESERVED
RESERVED
SR2CLK (P_PGP05)
A15
A14
A13
A12
A11
A10
PLLGND
PLLVDD
A09
A08
A07
VDD
A06
A05
A04
A03
A02
A01
A00
D7
D6
D5
D4
MIC_BIAS
LINE_IN
RES2#
MIC_IN
VC
VREF
LINE_OUT_M
LINE_OUT_P
ASPKR
AVDD
AGND
HD7 (PC7)
HD6 (PC6)
VDD
HD5 (PC5)
VSS
HD4 (PC4)
HD3 (PC3)
HD2 (PC2)
VDD
HD1 (PC1)
HD0 (PC0)
PHS2
RD#
WT#
NMIP
VDD
XTLO
XTLI
CLKIN
DV1TP
TESTP
HINT (PB7)
VDD
PB6
A18 (PB5)
PA4
PA5
PA6
NVMCLK (PA7)
RES1#
SR3OUT
SR3IN (P_PX01)
MCLKOUT (P_PB00)
SA2CLK (P_PX05)
VSS
SR2IO (P_PX06)
VDD
SR4OUT (P_PX00)
SA1CLK (P_PX02)
IA1CLK (P_PX03)
SR4IN
PD7
NOXYCK
XXCLK
IASLEEP (P_PF05)
P_PA07
P_GP01
VDD
P_PA03
P_PA00
SR1IO (PX07)
LPO
VDD
BD2CLK
VGG
CLKOUT
D0
D1
D2
VSS
D3
CX06827
PARALLEL INTERFACE
(PARIF PIN = HIGH)
Figure 3-2. CX06827 ACF 144-Pin TQFP Pin Signals for Parallel Interface (PARIF = High)
SC56D Single Chip ACF Modem Data Sheet
3-4 Conexant 101098C
Table 3-1. CX06827 ACF 144-Pin TQFP Pin Signals for Parallel Interface (PARIF = High)
Pin Signal Label I/O I/O Type Interface Pin Signal Label I/O I/O Type Interface
1 DVDD P PWR +3.3V 73 D4 I/O It/Ot2 EB: D4
2 CNTLSIN I Itpd ACF: SR1IO 74 D5 I/O It/Ot2 EB: D5
3 MCLKIN I Ipd ACF: MCLKOUT
through 33 ohms
75 D6 I/O It/Ot2 EB: D6
4 TXSIN I Itpd ACF: SR4OUT 76 D7 I/O It/Ot2 EB: D7
5 SCLK O Ot2 ACF: IA1CLK through
33 ohms
77 A00 O Ith/Ot8 EB: A00
6 RXOUT O Ot2 ACF: SR4IN 78 A01 O Ith/Ot8 EB: A01
7 STROBE O Ot2 ACF:SA1CLK through
33 ohms
79 A02 O Ith/Ot8 EB: A02
8 M_RELAY_A O Ot2 NC 80 A03 O Ith/Ot8 EB: A03
9 AGND G AGND AGND 81 A04 O Ith/Ot8 EB: A04
10 DVDD P PWR +3.3V 82 A05 O Ith/Ot8 EB: A05
11 DVSS G GND GND 83 A06 O Ith/Ot8 EB: A06
12 M_ACT_90 I Itpu NC 84 VDD P PWR +3.3V
13 DLPBK_BAR I It NC 85 A07 O Ith/Ot8 EB: A07
14 SLEEP_IN I Itpd ACF: IASLEEP 86 A08 O Ith/Ot8 EB: A08
15 AGND G AGND AGND 87 A09 O Ith/Ot8 EB: A09
16 PARIF (MK0) I Itpu NC (Parallel Host) 88 PLLVDD P PWR +3.3V and to GND
through 1 uF
17 HA0 (PD0) I Ithpd/Ot2 HB: HA0 89 PLLGND G GND GND
18 HA1 (PD1) I Ithpd/Ot2 HB: HA1 90 A10 O Ith/Ot8 EB: A10
19 HA2 (PD2) I Ithpd/Ot2 HB: HA2 91 A11 O Ith/Ot8 EB: A11
20 PD3 I Ith/Ot2 +3.3V through 47 K 92 A12 O Ith/Ot8 EB: A12
21 HCS# (PD4) I It HB: CS# 93 A13 O Ith/Ot8 EB: A13
22 HWT# (PD5) I Ithpu HB: WT# 94 A14 O Ith/Ot8 EB: A14
23 HRD# (PD6) I Ithpu HB: RD# 95 A15 O Ith/Ot8 EB: A15
24 OH# (PE0) I/O It/Ot8 DAA: Off-Hook Relay
Circuit
96 SR2CLK (P_PGP05) I Itpu/Ot2 VC: M_SCK
25 PE1 I/O It/Ot2 NC 97 RESERVED I/O Idd/Odd NC
26 PE2 I/O It/Ot2 NC 98 RESERVED I/O Idd/Odd NC
27 NVMDATA (PE3) I/O It/Ot2 NVRAM: SDA 99 RESERVED O Odpc NC
28 LCS (PE4) I It/Ot2 DAA: Line Current
Sense Circuit
100 RESERVED O Odpc NC
29 VDD P PWR +3.3V 101 RESERVED O It/Ot2 NC
30 PE5 I It/Ot2 +3.3V through 47 K 102 A16 (PB0) O It/Ot2 EB: A16
31 PE6 I/O It/Ot2 NC 103 VDD P PWR +3.3V
32 PE7 I It/Ot8 +3.3V through 47 K 104 PB1 I/O It/Ot2 NC
33 RING (PA0) I It/Ot2 DAA: Ring Detect
Circuit
105 ROMSEL# (PB2) O Ot2 EB: ROM CE#
34 PA1 I/O It/Ot2 NC 106 GND G GND GND
35 PA2 I/O It/Ot2 NC 107 RAMSEL# (PB3) O It/Ot2 EB: RAM CS#
36 PA3 I/O Itpu/Ot2 NC 108 A17 (PB4) O It/Ot2 EB: A17
37 PA4 I/O Itpu/Ot2 NC 109 A18 (PB5) O It/Ot2 EB: A18
38 PA5 I/O It/Ot2 NC 110 PB6 I/O It/Ot2 NC
39 PA6 I/O It/Ot2 NC 111 VDD P PWR +3.3V
40 NVMCLK (PA7) O It/Ot2 NVRAM: SCL 112 HINT (PB7) O It/Ot8 HB: HINT
41 RES1# I It HB: RESET# 113 TESTP I Itpu NC
42 SR3OUT O Ot2 VC: M_TXSIN 114 DV1TP I Itpu NC
43 SR3IN (P_PX01) I Itk/Ot2 VC: M_RXOUT 115 CLKIN I It NC
44 MCLKOUT (P_PB00) O It/Ot2 Through 33 ohms to
ACF:MCLKIN and VC:
M_CLKIN
116 XTLI I Ix Crystal Circuit
45 SA2CLK (P_PX05) I Itpu/Ot2 VC: M_STROBE 117 XTLO O Ox Crystal Circuit
46 GND G GND GND 118 VDD P PWR +3.3V
47 SR2IO (P_PX06) O It/Ot2 VC: M_CNTRLSIN 119 NMIP I Ithpu +3.3V
48 VDD P PWR +3.3V 120 WT# O It/Ot2 EB: WRITE#
49 SR4OUT (P_PX00) O Itk/Ot2 ACF: TXSIN 121 RD# O It/Ot2 EB: READ#
50 SA1CLK (P_PX02) I Itpu/Ot2 ACF: STROBE through
33 ohms
122 PHS2 O Ot2 NC
SC56D Single Chip ACF Modem Data Sheet
101098C Conexant 3-5
Table 3-1. CX06827 ACF 144-Pin TQFP Pin Signals for Parallel Interface (PARIF = High) (Continued)
Pin Signal Label I/O I/O Type Interface Pin Signal Label I/O I/O Type Interface
51 IA1CLK (P_PX03) I Itpu/Ot2 ACF: SCLK through 33
ohms
123 HD0 (PC0) I/O Ith/Ot8 HB: HD0
52 SR4IN I Itk/Ot2 ACF: RXOUT 124 HD1 (PC1) I/O Ith/Ot8 HB: HD1
53 PD7 I/O It/Ot2 NC 125 VDD P PWR +3.3V
54 NOXYCK I Itpu GND 126 HD2 (PC2) I/O Ith/Ot8 HB: HD2
55 XXCLK O It/Ot2 NC 127 HD3 (PC3) I/O Ith/Ot8 HB: HD3
56 IASLEEP (P_PF05) O Ot2 VC: SLEEP 128 HD4 (PC4) I/O Ith/Ot8 HB: HD4
57 P_PA07 O Ot2 NC 129 GND G GND GND
58 P_GP01 I It NC 130 HD5 (PC5) I/O Ith/Ot8 HB: HD5
59 VDD P PWR +3.3V 131 VDD P PWR +3.3V
60 P_PA03 O Ot2 NC 132 HD6 (PC6) I/O Ith/Ot8 HB: HD6
61 P_PA00 I/O Itpu/Ot2 NC 133 HD7 (PC7) I/O Ith/Ot8 HB: HD7
62 SR1IO (P_PX07) O It/Ot2 ACF: CNTLSIN 134 AGND G AGND AGND
63 LPO I Itpu/Ot2 +3.3V through 240K 135 AVDD P PWR +3.3VA (Filtered)
64 VDD P PWR +3.3V 136 ASPKR O O(DF) AI: Speaker Circuit
65 BD2CLK O Itpu/Ot2 NC 137 LINE_OUT_P O O(DF) DAA: TXAP
66 VGG R REF +5V or +3.3V 138 LINE_OUT_M O O(DF) DAA: TXAM
67 CLKOUT O It/Ot2 NC 139 VREF R REF AGND through C circuit
68 D0 I/O It/Ot2 EB: D0 140 VC R REF AGND through C circuit
69 D1 I/O It/Ot2 EB: D1 141 MIC_IN I I(DA) NC
70 D2 I/O It/Ot2 EB: D2 142 RES2# I It HB: RESET#
71 GND G GND GND 143 LINE_IN I I(DA) DAA: RXA
72 D3 I/O It/Ot2 EB: D3 144 MIC_BIAS O Oa NC
Notes:
1. I/O Types: See Table 3-4.
2. Interface Legend:
EB Expansion Bus
HB Host Bus
NC No external connection
VC Voice Codec
SC56D Single Chip ACF Modem Data Sheet
3-6 Conexant 101098C
XTLI
XTLO
CLKIN
CLKOUT
NMIP
PARIF (MK0)
NOXYCK
XTCLK# (P_GP01)
RDCLK# (P_PA07)
TDCLK# (P_PA03)
TXD# (PA2)
RXD# (PA6)
CTS# (PC1)
DSR# (PC0)
RLSD# (PC2)
RI# (PC5)
DTR# (PD4)
RTS# (PD6)
DTRIND# (PD0)
AAIND# (PC4)
RES1#
RES2#
LPO
PC3
PC7
PD3
PE5
PE7
XXCLK
BD2CLK
DV1TP
PHS2
TESTP
P_PA00
PA1
PA3
PA4
PA5
PB1
PB6
PD7
PE1
PE2
PE6
PB7
PC6
PD1
PD2
PD5
VGG
VDD
VDD
VDD
VDD
VDD
VDD
VDD
VDD
VDD
VDD
DVDD
DVDD
AVDD
VSS
VSS
VSS
VSS
DVSS
AGND
AGND
AGND
116
117
115
67
119
16
54
58
57
60
35
39
124
123
126
130
21
23
17
128
41
142
63
127
133
20
30
32
55
65
114
122
113
61
34
36
37
38
104
110
53
25
26
31
112
132
18
19
22
66
29
48
64
84
103
111
125
131
59
118
1
10
135
46
71
106
129
11
9
15
134
SERIAL DTE
INTERFACE
NVMCLK (PA7)
NVMDATA (PE3)
OH# (PE0)
LCS (PE4)
RING (PA0)
LINE_OUT_P
LINE_OUT_M
LINE_IN
ASPKR
MIC_IN
MIC_BIAS
M_RELAY_A
M_ACT_90
DLPBK_BAR
VREF
VC
SLEEP_IN
MCLKIN
CNTLSIN
RXOUT
TXSIN
STROBE
SCLK
IA1CLK (P_PX03)
SA1CLK (P_PX02)
SR4OUT (P_PX00)
SR4IN
SR1IO (P_PX07)
IASLEEP (P_PF05)
MCLKOUT (P_PB00)
SR2CLK (P_PGP05)
SA2CLK (P_PX05)
SR3OUT
SR3IN (P_PX01)
SR2IO (P_PX06)
PLLVDD
PLLGND
A00
A01
A02
A03
A04
A05
A06
A07
A08
A09
A10
A11
A12
A13
A14
A15
A16 (PB0)
A17 (PB4)
A18 (PB5)
D0
D1
D2
D3
D4
D5
D6
D7
RD#
WT#
RAMSEL# (PB3)
ROMSEL# (PB2)
RESERVED
RESERVED
RESERVED
RESERVED
RESERVED
40
27
24
28
33
137
138
143
136
141
144
8
12
13
139
140
14
3
2
6
4
7
5
51
50
49
52
62
56
44
96
45
42
43
47
88
89
77
78
79
80
81
82
83
85
86
87
90
91
92
93
94
95
102
108
109
68
69
70
72
73
74
75
76
121
120
107
105
97
98
99
100
101
101098_F3-3_HI_CX06827 144T SER
+3.3V
CX06827
SINGLE CHIP
ACF MODEM
144-PIN TQFP
SERIAL
INTERFACE
(PARIF = LOW)
1uF
NC
CRYSTAL
CIRCUIT
EXTERNAL
RAM AND ROM
LED
INTERFACE
RESET CIRCUIT
DAA
+3.3V OR +5V
CX20437
VOICE CODEC
(VC)
(OPTIONAL)
+3.3V
NC
NC
+3.3V
240K
47K
47K
47K
47K
47K
SCL
SDA
+3.3V
EEPROM (OPTIONAL)
OH#
LCS
RING
TXAP
TXAM
RXA
NC
SPEAKER CIRCUIT
+3.3V
+3.3V
+3.3V
+3.3V
+3.3V
33
33
33
SLEEP
M_CLKIN
M_SCK
M_STROBE
M_TXSIN
M_RXOUT
M_CNTRLSIN
NC
+3.3V A (FILTERED)
NC
(SERIAL DTE
INTERFACE ONLY)
NC
0.1
AGND
10
0.1
AGND
10
Figure 3-3. CX06827 ACF Hardware Signals for Serial Interface (PARIF = Low)
SC56D Single Chip ACF Modem Data Sheet
101098C Conexant 3-7
101098 F3-4 PO CX06827 144T Ser
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
108
107
106
105
104
103
102
101
100
99
98
97
96
95
94
93
92
91
90
89
88
87
86
85
84
83
82
81
80
79
78
77
76
75
74
73
144
143
142
141
140
139
138
137
136
135
134
133
132
131
130
129
128
127
126
125
124
123
122
121
120
119
118
117
116
115
114
113
112
111
110
109
DVDD
CNTLSIN
MCLKIN
TXSIN
SCLK
RXOUT
STROBE
M_RELAY_A
AGND
DVDD
DVSS
M_ACT_90
DLPBK_BAR
SLEEP_IN
AGND
PARIF (MK0)
DTRIND# (PD0)
PD1
PD2
PD3
DTR# (PD4)
PD5
RTS# (PD6)
OH# (PE0)
PE1
PE2
NVMDATA (PE3)
LCS (PE4)
VDD
PE5
PE6
PE7
RING (PA0)
PA1
TXD# (PA2)
PA3
A17 (PB4)
RAMSEL# (PB3)
VSS
ROMSEL# (PB2)
PB1
VDD
A16 (PB0)
RESERVED
RESERVED
RESERVED
RESERVED
RESERVED
SR2CLK (P_PGP05)
A15
A14
A13
A12
A11
A10
PLLGND
PLLVDD
A09
A08
A07
VDD
A06
A05
A04
A03
A02
A01
A00
D7
D6
D5
D4
MIC_BIAS
LINE_IN
RES2#
MIC_IN
VC
VREF
LINE_OUT_M
LINE_OUT_P
ASPKR
AVDD
AGND
PC7
PC6
VDD
RI# (PC5)
VSS
AAIND# (PC4)
PC3
RLSD# (PC2)
VDD
CTS# (PC1)
DSR# (PC0)
PHS2
RD#
WT#
NMIP
VDD
XTLO
XTLI
CLKIN
DV1TP
TESTP
PB7
VDD
PB6
A18 (PB5)
PA4
PA5
RXD# (PA6)
NVMCLK (PA7)
RES1#
SR3OUT
SR3IN (P_PX01)
MCLKOUT (P_PB00)
SA2CLK (P_PX05)
VSS
SR2IO (P_PX06)
VDD
SR4OUT (PX00)
SA1CLK (P_PX02)
IA1CLK (P_PX03)
SR4IN
PD7
NOXYCK
XXCLK
IASLEEP (P_PF05)
RDCLK# (P_PA07)
XTCLK# (P_GP01)
VDD
TDCLK# (P_PA03)
P_PA00
SR1IO (P_PX07)
LPO
VDD
BD2CLK
VGG
CLKOUT
D0
D1
D2
VSS
D3
CX06827
SERIAL INTERFACE
(PARIF PIN = LOW)
Figure 3-4. CX06827 ACF 144-Pin TQFP Pin Signals for Serial Interface (PARIF = Low)
SC56D Single Chip ACF Modem Data Sheet
3-8 Conexant 101098C
Table 3-2. CX06827 ACF 144-Pin TQFP Pin Signals for Serial Interface (PARIF = Low)
Pin Signal Label I/O I/O Type Interface Pin Signal Label I/O I/O Type Interface
1 DVDD P PWR +3.3V 73 D4 I/O It/Ot2 EB: D4
2 CNTLSIN I Itpd ACF: SR1IO 74 D5 I/O It/Ot2 EB: D5
3 MCLKIN I Ipd ACF: MCLKOUT
through 33 ohms
75 D6 I/O It/Ot2 EB: D6
4 TXSIN I Itpd ACF: SR4OUT 76 D7 I/O It/Ot2 EB: D7
5 SCLK O Ot2 ACF: IA1CLK through
33 ohms
77 A00 O Ith/Ot8 EB: A00
6 RXOUT O Ot2 ACF: SR4IN 78 A01 O Ith/Ot8 EB: A01
7 STROBE O Ot2 ACF:SA1CLK through
33 ohms
79 A02 O Ith/Ot8 EB: A02
8 M_RELAY_A O Ot2 NC 80 A03 O Ith/Ot8 EB: A03
9 AGND G AGND AGND 81 A04 O Ith/Ot8 EB: A04
10 DVDD P PWR +3.3V 82 A05 O Ith/Ot8 EB: A05
11 DVSS G GND GND 83 A06 O Ith/Ot8 EB: A06
12 M_ACT_90 I Itpu NC 84 VDD P PWR +3.3V
13 DLPBK_BAR I It NC 85 A07 O Ith/Ot8 EB: A07
14 SLEEP_IN I Itpd ACF: IASLEEP 86 A08 O Ith/Ot8 EB: A08
15 AGND G AGND AGND 87 A09 O Ith/Ot8 EB: A09
16 PARIF (MK0) I Itpu GND (Serial DTE) 88 PLLVDD P PWR +3.3V and to GND
through 1 uF
17 DTRIND# (PD0) O Ithpd/Ot2 LED: DTRIND# 89 PLLGND G GND GND
18 PD1 I/O Ithpd/Ot2 NC 90 A10 O Ith/Ot8 EB: A10
19 PD2 I/O Ithpd/Ot2 NC 91 A11 O Ith/Ot8 EB: A11
20 PD3 I Ith/Ot2 +3.3V through 47 K 92 A12 O Ith/Ot8 EB: A12
21 DTR# (PD4) I It DTE: DTR# 93 A13 O Ith/Ot8 EB: A13
22 PD5 I/O Ithpu NC 94 A14 O Ith/Ot8 EB: A14
23 RTS# (PD6) I Ithpu DTE: RTS# 95 A15 O Ith/Ot8 EB: A15
24 OH# (PE0) I/O It/Ot8 DAA: Off-Hook Relay
Circuit
96 SR2CLK (P_PGP05) I Itpu/Ot2 VC: M_SCK
25 PE1 I/O It/Ot2 NC 97 RESERVED I/O Idd/Odd NC
26 PE2 I/O It/Ot2 NC 98 RESERVED I/O Idd/Odd NC
27 NVMDATA (PE3) I/O It/Ot2 NVRAM: SDA 99 RESERVED O Odpc NC
28 LCS (PE4) I It/Ot2 DAA: Line Current
Sense Circuit
100 RESERVED O Odpc NC
29 VDD P PWR +3.3V 101 RESERVED O It/Ot2 NC
30 PE5 I It/Ot2 +3.3V through 47 K 102 A16 (PB0) O It/Ot2 EB: A16
31 PE6 I/O It/Ot2 NC 103 VDD P PWR +3.3V
32 PE7 I It/Ot8 +3.3V through 47 K 104 PB1 I/O It/Ot2 NC
33 RING (PA0) I It/Ot2 DAA: Ring Detect
Circuit
105 ROMSEL# (PB2) O Ot2 EB: ROM CE#
34 PA1 I/O It/Ot2 NC 106 GND G GND GND
35 TXD# (PA2) I It/Ot2 DTE: TXD# 107 RAMSEL# (PB3) O It/Ot2 EB: RAM CS#
36 PA3 I/O Itpu/Ot2 NC 108 A17 (PB4) O It/Ot2 EB: A17
37 PA4 I/O Itpu/Ot2 NC 109 A18 (PB5) O It/Ot2 EB: A18
38 PA5 I/O It/Ot2 NC 110 PB6 I/O It/Ot2 NC
39 RXD# (PA6) O It/Ot2 DTE: RXD# 111 VDD P PWR +3.3V
40 NVMCLK (PA7) O It/Ot2 NVRAM: SCL 112 PB7 O It/Ot8 NC
41 RES1# I It Reset Circuit 113 TESTP I Itpu NC
42 SR3OUT O Ot2 VC: M_TXSIN 114 DV1TP I Itpu NC
43 SR3IN (P_PX01) I Itk/Ot2 VC: M_RXOUT 115 CLKIN I It NC
44 MCLKOUT (P_PB00) O It/Ot2 Through 33 ohms to
ACF:MCLKIN and VC:
M_CLKIN
116 XTLI I Ix Crystal Circuit
45 SA2CLK (P_PX05) I Itpu/Ot2 VC: M_STROBE 117 XTLO O Ox Crystal Circuit
46 GND G GND GND 118 VDD P PWR +3.3V
47 SR2IO (P_PX06) O It/Ot2 VC: M_CNTRLSIN 119 NMIP I Ithpu +3.3V
48 VDD P PWR +3.3V 120 WT# O It/Ot2 EB: WRITE#
49 SR4OUT (P_PX00) O Itk/Ot2 ACF: TXSIN 121 RD# O It/Ot2 EB: READ#
50 SA1CLK (P_PX02) I Itpu/Ot2 ACF: STROBE through
33 ohms
122 PHS2 O Ot2 NC
SC56D Single Chip ACF Modem Data Sheet
101098C Conexant 3-9
Table 3-2. CX06827 ACF 144-Pin TQFP Pin Signals for Serial Interface (PARIF = Low) (Continued)
Pin Signal Label I/O I/O Type Interface Pin Signal Label I/O I/O Type Interface
51 IA1CLK (P_PX03) I Itpu/Ot2 ACF: SCLK through 33
ohms
123 DSR# (PC0) O Ith/Ot8 DTE: DSR#
52 SR4IN I Itk/Ot2 ACF: RXOUT 124 CTS# (PC1) O Ith/Ot8 DTE: CTS#
53 PD7 I/O It/Ot2 NC 125 VDD P PWR +3.3V
54 NOXYCK I Itpu GND 126 RLSD# (PC2) O Ith/Ot8 DTE: RLSD#
55 XXCLK O It/Ot2 NC 127 PC3 I/O Ith/Ot8 +3.3V through 47 K
56 IASLEEP (P_PF05) O Ot2 VC: SLEEP 128 AAIND# (PC4) O Ith/Ot8 LED: AAIND#
57 RDCLK# (P_PA07) O Ot2 DTE: RDCLK# 129 GND G GND GND
58 XTCLK# (P_GP01) I It DTE: XTCLK# 130 RI# (PC5) O Ith/Ot8 DTE: RI#
59 VDD P PWR +3.3V 131 VDD P PWR +3.3V
60 TDCLK# (P_PA03) O Ot2 DTE: TDCLK# 132 PC6 I/O Ith/Ot8 HB: HD6
61 P_PA00 I/O Itpu/Ot2 NC 133 PC7 I/O Ith/Ot8 +3.3V through 47 K
62 SR1IO (P_PX07) O It/Ot2 ACF: CNTLSIN 134 AGND G AGND AGND
63 LPO I Itpu/Ot2 +3.3V through 240K 135 AVDD P PWR +3.3VA (Filtered)
64 VDD P PWR +3.3V 136 ASPKR O O(DF) AI: Speaker Circuit
65 BD2CLK O Itpu/Ot2 NC 137 LINE_OUT_P O O(DF) DAA: TXAP
66 VGG R REF +5V or +3.3V 138 LINE_OUT_M O O(DF) DAA: TXAM
67 CLKOUT O It/Ot2 NC 139 VREF R REF AGND through C circuit
68 D0 I/O It/Ot2 EB: D0 140 VC R REF AGND through C circuit
69 D1 I/O It/Ot2 EB: D1 141 MIC_IN I I(DA) NC
70 D2 I/O It/Ot2 EB: D2 142 RES2# I
71 GND G GND GND 143 LINE_IN I I(DA) DAA: RXA
72 D3 I/O It/Ot2 EB: D3 144 MIC_BIAS O Oa NC
Notes:
1. I/O Types: See Table 3-4.
2. Interface Legend:
EB Expansion Bus
HB Host Bus
NC No external connection
VC Voice Codec
SC56D Single Chip ACF Modem Data Sheet
3-10 Conexant 101098C
Table 3-3. CX06827 ACF Pin Signal Definitions
Label Pin I/O I/O Type Signal Name/Description
COMMON TO PARALLEL HOST AND SERIAL DTE INTERFACE CONFIGURATIONS
System
XTLI,
XTLO
116,
117
I,
O
Ix,
Ox
Crystal In and Crystal Out. If an external 28.224 MHz crystal circuit is used
instead of an external clock circuit, connect XTLI and XTLO to the external
crystal circuit and leave CLKIN open.
CLKIN 115 I It Clock In. If an external 28.224 MHz clock circuit is used instead of an
external crystal circuit, connect CLKIN to the clock output and leave XTLI
and XTLO open.
CLKOUT 67 O It/Ot2 Clock Out. 28.224 MHz output clock. Leave open.
NOXYCK 54
PARIF 16 I Itpu Parallel/Serial Interface Select. PARIF input high (open) selects parallel
host interface operation. PARIF low (GND) selects serial DTE interface
operation.
NMI# 119 I Ithpu Non-Maskable Interrupt. Not used. Connect to +3.3V.
RES1#
RES2#
41
142
IIt Reset. The active low RESET# (RES1# and RES2#) input resets the ACF
logic, and restores the saved configuration from serial EEPROM or returns
the modem to the factory default values if NVRAM is not present.
RESET# low holds the modem in the reset state; RESET# going high
releases the modem from the reset state. After application of VDD, RESET#
must be held low for at least 15 ms after the VDD power reaches operating
range. The modem device set is ready to use 25 ms after the low-to-high
transition of RESET#.
For parallel Interface, connect RESET# input to the host bus RESET line
through an inverter.
For serial Interface, connect RESET# input to a reset switch circuit.
Power and Ground
VGG 66 P PWRG I/O Signaling Voltage Source. Connect to +5V or +3.3V.
VDD 29, 48, 59,
64, 66, 84,
103, 111,
118, 125,
131
PPWRDigital Supply Voltage for Digital Circuits. Connect to +3.3V.
DVDD 1, 10 P PWR Digital Supply Voltage for Analog Circuits. Connect to +3.3V
VSS 46, 71, 106,
129
GGND Digital Ground for Digital Circuits. Connect to digital ground (GND).
DVSS 11 G GND Digital Ground for Analog Circuits. Connect to digital ground (GND).
AGND 135 G AGND Analog Ground for Analog Circuits. Connect to analog ground (AGND).
PLLVDD 88 P PWR PLL Circuit Digital Supply Voltage. Connect to +3.3V and to AGND
through 1 µF.
PLLGND 89 G GND PLL Circuit Digital Ground. Connect to GND.
Serial EEPROM (NVRAM) Interface
NVMCLK (PA7) 40 O It/Ot2 NVRAM Clock. NVMCLK output high enables the EEPROM. Connect to
EEPROM SCL pin.
NVMDATA (PE3) 27 I/O It/Ot2 NVRAM Data. The NVMDATA pin supplies a serial data interface to the
EEPROM. Connect to EEPROM SDA pin and to +3.3V through 10 KΩ.
Not Used – Connect to +3.3V through Resistor
LPO 63 I I/O Low Power Oscillator. Not used. Connect to +3.3V through 240 KΩ.
PC3 127 I Ith/Ot2 Port PC3. Not used. Connect to +3.3V through 47K Ω.
PC7 133 I Ith/Ot2 Port PC7. Not used. Connect to +3.3V through 47K Ω.
PD3 20 I Ith/Ot2 Port PD7. Not used. Connect to +3.3V through 47K Ω.
PE5 30 I Ith/Ot2 Port PE5. Not used. Connect to +3.3V through 47K Ω.
PE7 32 I Ith/Ot2 Port PE7. Not used. Connect to +3.3V through 47K Ω.
SC56D Single Chip ACF Modem Data Sheet
101098C Conexant 3-11
Table 3-3. CX06827 ACF Pin Signal Definitions (Continued)
Label Pin I/O I/O Type Signal Name/Description
External Bus Interface
A00-A06,
A07-A09,
A10-A15,
A16 (PB0),
A17 (PB4),
A18 (PB5)
77-83,
85-87,
90-95,
102,
108,
109
O,
O,
O,
O,
O,
O
It/Ot8,
It/Ot8,
It/Ot2,
It/Ot2,
It/Ot2,
It/Ot2
Address Lines 0-18. A0-A18 are the address output lines used to access
external memory; up to 4 Mbits (512k bytes) ROM/flash ROM using A0-A18
and up to 1 Mbit (128k bytes) RAM using A0-A16.
D0-D2,
D3-D7
68-70,
72-76
I/O Ith/Ot2 Data Line 0-7. D0-D7 are bidirectional external memory bus data lines.
READ# 121 O It/Ot2 Read Enable. READ# output low enables data transfer from the selected
device to the D0-D7 lines.
WRITE# 120 O It/Ot2 Write Enable. WRITE# output low enables data transfer from the D0-D7
lines to the selected device.
RAMSEL# (PB3) 107 O It/Ot2 RAM Select. RAMSEL# (PB3, ES2) output low selects the external RAM.
ROMSEL# (PB2) 105 O Ot2 ROM Select. ROMSEL# (PB2, ES3) output low selects the external ROM.
TELEPHONE LINE/TELEPHONE/AUDIO INTERFACE SIGNALS AND REFERENCE VOLTAGE
OH# (PE4) 33 I It Off-Hook. Active low input used to indicate the telephone line is in use by
the local handset or an extension phone.
LCS (PE4) 28 I It Loop Current Sense. LCS is an active high input that indicates a handset
off-hook status.
RING (PA0) 33 I It Ring Frequency. A rising edge on the RING input initiates an internal ring
frequency measurement. The RING input from an external ring detect circuit
is monitored to determine when to wake up from sleep or stop mode. The
RING input is typically connected to the output of an optoisolator or
equivalent. The idle state (no ringing) output of the ring detect circuit should
be low.
LINE_OUT_P,
LINE_OUT_M
137,
138
O,
O
O(DF) Transmit Analog 1 and 2. The LINE_OUT_P and LINE_OUT_M outputs
are differential outputs 180 degrees out of phase with each other. Each
output can drive a 300 Ω load. Connect LINE_OUT_P and LINE_OUT_M to
the DAA telephone line interface transmit circuit.
LINE_IN I(DA) Receive Analog. LINE_IN is a single-ended input from the telephone line
interface or an optional external hybrid circuit with 70K Ω input impedance.
Connect LINE_IN to the DAA telephone line interface receive circuit.
VREF 139 R REF High Voltage Reference. Connect to AGND through 10 µF (polarized, +
terminal to VREF) and 0.1 µF (ceramic) in parallel. Ensure a very close
proximity between these capacitors and VREF pin. Use a short path and a
wide trace to AGND pin.
VC 140 R REF Low Voltage Reference. Connect to AGND through 10 µF (polarized, +
terminal to VC) and 0.1 µF (ceramic) in parallel. Ensure a very close
proximity between these capacitors and VC pin. Use a short path and a
wide trace to AGND pin.
ASPKR 136 O O(DF) Speaker Analog Output. The ASPKR analog output can originate from one
of five different sources: RIN, TELIN, MICM or MICV or from the MDP’s
internal voice playback mode. The ASPKR on/off and three levels of
attenuation are controlled by bits in DSP RAM. When the speaker is turned
off, the ASPKR output is clamped to the voltage at the VC pin. The ASPKR
output can drive an impedance as low as 300 ohms. In a typical application,
the ASPKR output is an input to an external LM386 audio power amplifier.
MIC_M 141 I I(DA) Not Used. Leave open.
MIC_BIAS 144 O Oa Not Used. Leave open.
M_RELAYA 8 O Ot Not Used. Leave open.
M_ACT90 12 I Itpu Not Used. Leave open.
DLPBK_BAR 13 I It Not Used. Leave open.
SC56D Single Chip ACF Modem Data Sheet
3-12 Conexant 101098C
Table 3-3. CX06827 ACF Pin Signal Definitions (Continued)
Label Pin I/O I/O Type Signal Name/Description
ACF Interconnect and Optional CX20437 VC Interface
SLEEP_IN 14 I Itpd Modem Codec Sleep In. Connect to ACF: IASLEEP pin.
MCLKIN 3 I Ipd Modem Codec Serial Clock In. Connect to ACF: MCLKOUT pin through
33 Ω.
CNTLSIN 2 I Itpd Modem Codec Serial Control In. Connect to ACF: SR1IO pin.
RXOUT 6 O Ot2 Modem Codec Serial Receive Data Out. Connect to ACF: SR4IN pin.
TXSIN 4 I Itpd Modem Codec Serial Transmit Data In. Connect to ACF: SR4OUT pin.
STROBE 7 O Ot2 Modem Codec Serial Frame Sync Out. Connect to ACF: SA1CLK pin
through 33 Ω.
SCLK 5 O Ot2 Modem Codec Serial Clock Out. Connect to ACF: IA1CLK pin through
33 Ω.
IA1CLK (P_PX03) 51 I Itpu/Ot2 DSP Modem Serial Clock In. Connect to ACF: SCLK pin through 33 Ω.
SA1CLK (P_PX02) 50 I Itpu/Ot2 DSP Modem Serial Frame Sync In. Connect to ACF: STROBE pin through
33 Ω.
SR4OUT (P_PX00) 49 O Itk/Ot2 DSP Modem Serial Transmit Data Out. Connect to ACF: TXSIN pin.
SR4IN 52 I Itk/Ot2 DSP Modem Serial Receive Data In. Connect to ACF: RXOUT pin.
IASLEEP (P_PF05) 56 O Ot2 DSP Sleep Out. Connect to ACF: SLEEP_IN pin and to VC SLEEP pin.
M_CLKOUT (P_PB00) 44 O It/Ot2 DSP Master Serial Clock Out. Connect through 33 Ω to ACF: MCLKIN pin
and to VC M_CLKIN pin.
SR2CLK (P_PGP05) 96 I Itpu/Ot2 DSP Voice Serial Clock In. Connect to VC M_SCK pin. Leave open if VC is
not installed.
SA2CLK (P_PX05) 45 I Itpu/Ot2 DSP Voice Serial Frame Sync In. Connect to VC M_STROBE pin. Leave
open if VC is not installed.
SR3OUT 42 O Ot2 DSP Voice Serial Transmit Data Out. Connect to VC M_TXSIN pin. Leave
open if VC is not installed.
SR3IN (P_PX01) 43 I Itk/Ot2 DSP Voice Serial Receive Data In. Connect to VC M_RXOUT pin. Leave
open if VC is not installed.
SR2IO (P_PX06) 47 O It/Ot2 DSP Voice Serial Control Out. Connect to VC M_CNTRLSIN pin. Leave
open if VC is not installed.
Not Used – Leave Open
P_PA00 61 I/O Itpu/Ot2 Not Used. Leave open.
XXCLK 55 O It/Ot2 Not Used. Leave open.
BD2CLK 65 O Itpu/Ot2 Not Used. Leave open.
DV1TP 114 I Itpu Not Used. Leave open.
PHS2 122 O Ot2 Not Used. Leave open.
TESTP 113 I Itpu Not Used. Leave open.
PA1 34 I/O It/Ot2 Port PA1. Not Used. Leave open.
PA3 36 I/O Itpu/Ot2 Port PA3. Not Used. Leave open.
PA4 37 I/O Itpu/Ot2 Port PA4. Not Used. Leave open.
PA5 35 I/O It/Ot2 Port PA5. Not Used. Leave open.
PB1 104 I/O It/Ot2 Port PB1. Not Used. Leave open.
PB6 110 I/O It/Ot2 Port PB6. Not Used. Leave open.
PD7 53 I/O It/Ot2 Port PD7. Not Used. Leave open.
PE1 25 I/O It/Ot2 Port PE1. Not Used. Leave open.
PE2 26 I/O It/Ot2 Port PE2. Not Used. Leave open.
PE6 31 I/O It/Ot2 Port PE6. Not Used. Leave open.
RESERVED 97-101 Reserved. Connected to internal circuitry. Leave open.
SC56D Single Chip ACF Modem Data Sheet
101098C Conexant 3-13
Table 3-3. CX06827 ACF Pin Signal Definitions (Continued)
Label Pin I/O I/O Type Signal Name/Description
PARALLEL HOST BUS CONFIGURATION ONLY (PARIF = HIGH)
Parallel Host Interface
HCS# (PD4) 21 I It Host Bus Chip Select. HCS# input low enables the MCU host bus
interface.
HRD# (PD6) 23 I Ithpu Host Bus Read. HRD# is an active low, read control input. When HCS# is
low, HRD# low allows the host to read status information or data from a
selected MCU register.
HWT# (PD5) 22 I Ithpu Host Bus Write. HWT# is an active low, write control input. When HCS# is
low, HWT# low allows the host to write data or control words into a selected
MCU register.
HINT (PB7) 112 O It/Ot8 Host Bus Interrupt. HINT output is set high when the receiver error flag,
received data available, transmitter holding register empty, or modem
status interrupt is asserted. HINT is reset low upon the appropriate interrupt
service or master reset operation.
HA0-HA2
(PD0-PD2)
17-19 I Ithpd/Ot2 Host Bus Address Lines 0-2. During a host read or write operation with
HCS# low, HA0-HA2 select an internal MCU 16550A-compatible register.
HD0-HD7
(PC0-PC7)
123-124,
126-128,
130-133
I/O Ith/Ot8 Host Bus Data Lines 0-7. HD0-HD7 are three-state input/output lines
providing bidirectional communication between the host and the MCU.
Data, control words, and status information are transferred over HD0-HD7.
Not Used (In Parallel Host Interface Configuration)
P_GP01 58 I It Port P_GP01. Not Used. Leave open.
P_PA03 60 O Ot2 Port P_PA03. Not Used. Leave open.
P_PA07 57 O Ot2 Port P_PA07. Not Used. Leave open.
PA2 35 I/O It/Ot2 Port PA2. Not Used. Leave open.
PA6 39 I/O It/Ot2 Port PA6. Not Used. Leave open.
SC56D Single Chip ACF Modem Data Sheet
3-14 Conexant 101098C
Table 3-3. CX06827 ACF Pin Signal Definitions (Continued)
Label Pin I/O I/O Type Signal Name/Description
SERIAL DTE INTERFACE CONFIGURATION ONLY (PARIF = LOW)
V.24 (EIA/TIA-232-E) DTE Serial Interface
These signals correspond functionally to V.24/EIA/TIA-232-E signals but are logically inverted.
XTCLK# (P_GP01) 58 I It/Ot2 External Data Clock. Synchronous External Transmit Data Clock input in
synchronous modes. Leave open if not used.
RDCLK# (P_PA07) 57 O Itpu/Ot2 Receive Data Clock. Synchronous Receive Data Clock output in
synchronous modes. The RDCLK frequency is the data rate (±0.01%) with
a duty cycle of 50±1%. Leave open if not used.
TDCLK# (P_PA03) 60 O Itpu/Ot2 Transmit Data Clock. Synchronous Transmit Data Clock output in
synchronous modes. The TDCLK# frequency is the data rate (±0.01%) with
a duty cycle of 50±1%. Leave open if not used.
TXD# (PA2) 35 I It/Ot2 Transmitted Data (EIA BA/ITU-T CT103). The DTE uses the TXD# line to
send data to the modem for transmission over the telephone line or to
transmit commands to the modem.
RXD# (PA6) 39 O It/Ot2 Received Data (EIA BB/ITU-T CT104). The modem uses the RXD# line to
send data received from the telephone line to the DTE and to send modem
responses to the DTE. During command mode, RXD# data represents the
modem responses to the DTE.
CTS# (PC1) 124 O Ith/Ot8 Clear To Send (EIA CB/ITU-T CT106). CTS# output ON (low) indicates
that the modem is ready to accept data from the DTE. In asynchronous
operation, in error correction or normal mode, CTS# is always ON (low)
unless RTS/CTS flow control is selected by the &Kn command.
In synchronous operation, the modem also holds CTS# ON during
asynchronous command state. The modem turns CTS# OFF immediately
upon going off-hook and holds CTS# OFF until both DSR# and RLSD# are
ON and the modem is ready to transmit and receive synchronous data. The
modem can also be commanded by the &Rn command to turn CTS# ON in
response to an RTS# OFF-to-ON transition.
DSR# (PC0) 123 O Ith/Ot8 Data Set Ready (EIA CC/ITU-T CT107). DSR# indicates modem status to
the DTE. DSR# OFF (high) indicates that the DTE is to disregard all signals
appearing on the interchange circuits except Ring Indicator (RI#). DSR#
output is controlled by the AT&Sn command.
RLSD# (PC2) 126 O Ith/Ot8 Received Line Signal Detector (EIA CF/ITU-T CT109). When AT&C0
command is not in effect, RLSD# output is ON when a carrier is detected
on the telephone line or OFF when carrier is not detected.
RI# (PC5) 130 O Ith/Ot8 Ring Indicator (EIA CE/ITU-T CT125). RI# output ON (low) indicates the
presence of an ON segment of a ring signal on the telephone line.
DTR# (PD4) 21 I It Data Terminal Ready (EIA CD/ITU-T CT108). The DTR# input is turned
ON (low) by the DTE when the DTE is ready to transmit or receive data.
DTR# ON prepares the modem to be connected to the telephone line, and
maintains the connection established by the DTE (manual answering) or
internally (automatic answering). DTR# OFF places the modem in the
disconnect state under control of the &Dn and &Qn commands.
RTS# (PD6) 23 I Ithpu Request To Send (EIA CA/ITU-T CT105). RTS# input ON (low) indicates
that the DTE is ready to send data to the modem. In the command state,
the modem ignores RTS#.
In asynchronous operation, the modem ignores RTS# unless RTS/CTS
flow control is selected by the &Kn command. In synchronous on-line
operation, the modem can be commanded by the &Rn command to ignore
RTS# or to respond to RTS# by turning on CTS# after the delay specified
by Register S26.
SC56D Single Chip ACF Modem Data Sheet
101098C Conexant 3-15
Table 3-3. CX06827 ACF Pin Signal Definitions (Continued)
Label Pin I/O I/O Type Signal Name/Description
SERIAL DTE INTERFACE CONFIGURATION ONLY (PARIF = LOW) (CONTINUED)
LED Indicator Interface
AAIND# (PC4) 128 O Ith/Ot8 Auto Answer Indicator. AAIND# output ON (low) corresponds to the
indicator on. AAIND# output is active when the modem is configured to
answer the ring automatically (ATS0 command ≠ 0).
DTRIND# (PD0) 17 O Ithpd/Ot2 DTR Indicator. DTRIND# output ON (low) corresponds to the indicator on.
The DTRIND# state reflects the DTR# output state except when the &D0
command is active, in which case DTRIND# is low.
Not Used (In Serial DTE Interface Configuration)
PC6 132 I/O Ith/Ot8 Port PC6. Not Used. Leave open.
PD1 18 I/O Ithpd/Ot2 Port PD1. Not Used. Leave open.
PD2 19 I/O Ithpd/Ot2 Port PD2. Not Used. Leave open.
PD5 22 I/O Ithpu Port PD5. Not Used. Leave open.
Notes:
1. I/O Types: See Table 3-4.
2. Interface Legend:
EB Expansion Bus
HB Host Bus
NC No internal pin connection
VC Voice Codec
RESERVED = No external connection allowed (may have internal connection).
SC56D Single Chip ACF Modem Data Sheet
3-16 Conexant 101098C
Table 3-4. CX06827 ACF I/O Type Definitions
I/O Type Description
Ix/Ox I/O, wire
It/Ot2 Digital input, +5V tolerant/ Digital output, 2 mA, ZINT = 120 Ω
Itk/Ot2 Digital input, +5V tolerant, keeper/ Digital output, 2 mA, ZINT = 120 Ω
Itpu/Ot2 Digital input, +5V tolerant, 75k Ω pull up/ Digital output, 2 mA, ZINT = 120 Ω
It/Ot8 Digital input, +5V tolerant,/ Digital output, 8 mA, ZINT = 50 Ω
Ithpd/Ot2 Digital input, +5V tolerant, hysteresis, 75k Ω pull down/ Digital output, 2 mA, ZINT = 120 Ω
Ith/Ot2 Digital input, +5V tolerant, hysteresis/Digital output, 2 mA, ZINT = 120 Ω
Ith/Ot8 Digital input, +5V tolerant, hysteresis/Digital output, 8 mA, ZINT = 50 Ω
It Digital input, +5V tolerant
Itk Digital input, +5V tolerant, keeper
Itkpu Digital input, +5V tolerant, keeper, 75k Ω pull up
Itpu Digital input, +5V tolerant, 75k Ω pull up
Ithpu Digital input, +5V tolerant, hysteresis, 75k Ω pull up
Ot2 Digital output, three-state, 2 mA, ZINT = 120 Ω
PWR VCC Power
PWRG VGG Power
GND Ground
NOTES:
1. See DC characteristics in Table 3-5.
2. I/O Type corresponds to the device Pad Type. The I/O column in signal interface tables refers to signal I/O direction used in the
application.
Table 3-5. CX06827 ACF DC Electrical Characteristics
Parameter Symbol Min. Typ. Max. Units Test Conditions
Input Voltage Low VIL
+5V tolerant 0 – 0.8 V
+5V tolerant hysteresis 0 – 0.3 *VGG V
Input Voltage High VIH – V
+5V tolerant 2 – 5.25 V
+5V tolerant hysteresis 0.7 * VDD – 5.25 V
Input Hysteresis VH – V
+3V hysteresis 0.5 – V
+5V tolerant, hysteresis 0.3 – V
Output Voltage Low VOL
ZINT = 120 Ω0 – 0.4 V IOL = 2 mA
ZINT = 50 Ω0 – 0.4 V IOL = 8 mA
Output Voltage High VOH – V
ZINT = 120 Ω2.4 – VDD V IOL = -2 mA
ZINT = 50 Ω2.4 – VDD V IOL = -8 mA
Pull-Up Resistance Rpu 50 – 200 kΩ
Pull-Down Resistance Rpd 50 – 200 kΩ
Test conditions unless otherwise noted:
1. Test Conditions unless otherwise stated: VDD = +3.3 ± 0.3 VDC; TA = 0°C to 70°C; external load = 50 pF.
SC56D Single Chip ACF Modem Data Sheet
101098C Conexant 3-17
3.2 CX20437 VC Hardware Pins and Signals (S Model)
Microphone and analog speaker interface signals, as well as telephone handset/headset interface signals are provided to
support functions such as speakerphone mode, telephone emulation, microphone voice record, speaker voice playback, and
call progress monitor.
VC hardware interface signals are shown by major interface in Figure 3-5, are shown by pin number in Figure 3-6, and are
listed by pin number in Table 3-6.
VC hardware interface signals are defined in Table 3-7.
VC pin signal DC electrical characteristics are defined in Table 3-8.
VC pin signal analog electrical characteristics are defined in Table 3-9.
SC56D Single Chip ACF Modem Data Sheet
3-18 Conexant 101098C
101098_F3-5_HI_20437
CX20437
VOICE CODEC
(VC)
32-PIN TQFP
AUDIO
CIRCUIT
NC
SPKOUT
MIC
TELOUT
TELIN
+3.3V
VAA (+3.3V)
14
19
21
23
20
22
18
4
17
25
5
28
26
6
27
IASLEEP
MCLKOUT
SR2CLK
SA2CLK
SR3OUT
SR3IN
SR2IO
SLEEP
M_CLKIN
M_SCK
M_STROBE
M_TXSIN
M_RXOUT
M_CNTRLSIN
POR
VDD
VDD
MAVDD
VSS
SET3V_BAR2
MAVSS
VSUB
M_DIG_SPEAKER
M_MIC_IN
M_SPKR_OUT
M_LINE_OUTM
M_LINE_OUTP
M_LINE_IN
VREF
VC
M_MIC_BIAS
M_RELAYA
M_RELAYB
M_ACT90
M_1BIT_OUT
D_LPBK_BAR
NC
NC
NC
2
13
3
10
9
14
11
12
15
24
16
29
30
31
7
8
32
NC
HANDSET
INTERFACE
NC
AGND
GN
D
FERRITE
VC_HAND
CX06827
ACF
RESET CIRCUIT
0.1
AGND
10
0.1
AGND
10
Figure 3-5. CX20437 VC Hardware Interface Signals
100491 F3-8 PO-CX20437
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
32
31
30
29
28
27
26
25
24
23
22
21
20
19
18
17
SLEEP
M_DIG_SPEAKER
M_SPKR_OUT
POR
MAVDD
MAVSS
NC
NC
M_RELAYA
M_STROBE
M_RXOUT
M_SCK
M_TXSIN
M_CLKIN
M_CNTRLSIN
VDD
M_LINE_OUTP
M_LINE_OUTM
VREF
VC
M_MIC_IN
M_LINE_IN
M_MIC_BIAS
M_RELAYB
NC
D_LPBK_BAR
M_1BIT_OUT
M_ACT90
VSS
VSUB
SET3V_BAR2
VDD
CX20437
Figure 3-6. CX20437 VC 32-Pin TQFP Pin Signals
SC56D Single Chip ACF Modem Data Sheet
101098C Conexant 3-19
Table 3-6. CX20437 VC 32-Pin TQFP Pin Signals
Pin Signal Label I/O I/O Type Interface
1 SLEEP I Itpd ACF: IASLEEP
2 M_DIG_SPEAKER O Ot2 NC
3 M_SPKR_OUT O Oa Speaker interface circuit
4 POR I Itpu Host: RESET# or reset circuit
5 MAVDD PWR VAA (+3.3V)
6 MAVSS AGND AGND
7NC NC
8NC NC
9 M_LINE_OUTP O Oa Handset interface circuit: TELOUT
10 M_LINE_OUTM O Oa NC
11 VREF REF AGND through capacitors
12 VC REF AGND through capacitors For handset interface, connect also to VC_HAND
through ferrite bead
13 M_MIC_IN I Ia Microphone interface circuit
14 M_LINE_IN I Ia Handset interface circuit: TELIN
15 M_MIC_BIAS NC
16 M_RELAYB NC
17 VDD PWR +3.3V
18 M_CNTRLSIN I Itpd ACF: V_CTRL
19 M_CLKIN I Itpd ACF: M_CLK
20 M_TXSIN I Itpd ACF: V_TXSIN
21 M_SCK O Ot2 ACF: V_SCLK
22 M_RXOUT O Ot2 ACF: V_RXOUT
23 M_STROBE O Ot2 ACF: V_STROBE
24 M_RELAYA O Ot2od NC
25 VDD PWR +3.3V
26 M_SET3V_BAR2 I Itpu GND
27 VSUB AGND AGND
28 VSS GND GND
29 M_ACT90 I Itpu NC
30 M_1BIT_OUT O Ot2 NC
31 D_LPBK_BAR I Itpu NC
32 NC NC
Notes:
1. I/O types:
Ia Analog input
It Digital input, TTL-compatible
Itpd Digital input, TTL-compatible, internal 75k ± 25k Ω pull-down
Itpu Digital input, TTL-compatible, internal 75k ± 25k Ω pull-up
Oa Analog output
Ot2 Digital output, TTL-compatible, 2 mA, ZINTERNAL = 120 Ω
Ot2od Digital output, TTL-compatible, 2 mA, open drain, ZINTERNAL = 120 Ω
AGND Analog Ground
GND Digital Ground
*See CX20437 VC DC Electrical Characteristics (Table 3-8) and CX20437 VC Analog Electrical Characteristics (Table 3-9).
SC56D Single Chip ACF Modem Data Sheet
3-20 Conexant 101098C
Table 3-7. CX20437 VC Pin Signal Definitions
Label Pin I/O Type Signal Name/Description
SYSTEM SIGNALS
VDD 17, 25 PWR Digital Power Supply. Connect to +3.3V and digital circuits power supply filter.
MAVDD 5 PWR Analog Power Supply. Connect to +3.3V and analog circuits power supply filter.
VSS 28 GND Digital Ground. Connect to GND.
MAVSS 6 AGND Analog Ground. Connect to AGND.
VSUB 27 GND Analog Ground. Connect to AGND.
POR 4 Itpu Power-On Reset. Active low reset input. Connect to Host RESET# or reset circuit.
SET3V_BAR2 26 Itpu Set +3.3V Analog Reference. Connect to GND.
ACF INTERCONNECT
SLEEP 1 Itpd IA Sleep. Active high sleep input. Connect to ACF IASLEEP pin.
M_CLKIN 19 Itpd Master Clock Input. Connect to ACF M_CLK pin.
M_SCK 21 Ot2 Serial Clock Output. Connect to ACF V_SCLK pin.
M_CNTRL_SIN 18 Itpd Control Input. Connect to ACF V_CTRL pin.
M_STROBE 23 Ot2 Serial Frame Sync. Connect to ACF V_STROBE pin.
M_TXSIN 20 Itpd Serial Transmit Data. Connect to ACF V_TXSIN pin.
M_RXOUT 22 Ot2 Serial Receive Data. Connect to ACF V_RXOUT pin.
MICROPHONE/SPEAKER INTERFACE
M_MIC_IN 13 I(DA) Microphone Input. Single-ended analog input from the microphone circuit.
M_SPKR_OUT 3 O(DF) Modem Speaker Analog Output. The M_SPKR_OUT analog output reflects the received
analog input signal. The M_SPKR_OUT on/off and three levels of attenuation are controlled
by bits in DSP RAM. When the speaker is turned off, the M_SPKR_OUT output is clamped
to the voltage at the VC pin. The M_SPKR_OUT output can drive an impedance as low as
300 ohms. In a typical application, the M_SPKR_OUT output is an input to an external
LM386 audio power amplifier.
HANDSET/HEADSET INTERFACE
M_LINE_OUTP 9 O(DF) Telephone Handset Out (TELOUT). Single-ended analog data output to the telephone
handset circuit. The output can drive a 300 Ω load.
M_LINE_IN 14 I(DA) Telephone Handset Out (TELIN). Single-ended analog data input from the telephone
handset circuit.
REFERENCE VOLTAGE
VREF 11 REF High Voltage Reference. Connect to AGND through 10 µF (polarized, + terminal to VREF)
and 0.1 µF (ceramic) in parallel. Ensure a very close proximity between these capacitors
and VREF pin. Use a short path and a wide trace to AGND pin.
VC 12 REF Low Voltage Reference. Connect to AGND through 10 µF (polarized, + terminal to VC) and
0.1 µF (ceramic) in parallel. Ensure a very close proximity between these capacitors and VC
pin. Use a short path and a wide trace to AGND pin.
For handset interface, also connect to handset interface circuit (VC_HAND) through a ferrite
bead.
SC56D Single Chip ACF Modem Data Sheet
101098C Conexant 3-21
Table 3-7. CX20437 VC Pin Signal Definitions (Continued)
Label Pin I/O Type Signal Name/Description
NOT USED
M_DIG_SPEAKER 2 Ot2 Not Used. Leave open.
M_LINE_OUTM 10 Oa Not Used. Leave open.
M_RELAYA 24 Ot Not Used. Leave open.
M_RELAYB 16 Ot Not Used. Leave open.
M_MIC_BIAS 15 Oa Not Used. Leave open.
M_ACT90 29 Itpu Not Used. Leave open.
M_1BIT_OUT 30 Ot2 Not Used. Leave open.
D_LPBK_BAR 31 It Not Used. Leave open.
NC 7, 8, 32 NC Internal No Connect. Leave open.
Notes:
1. I/O types*:
Ia Analog input
It Digital input, TTL-compatible
Itpd Digital input, TTL-compatible, internal 75k ± 25k Ω pull-down
Itpu Digital input, TTL-compatible, internal 75k ± 25k Ω pull-up
Oa Analog output
Ot2 Digital output, TTL-compatible, 2 mA, ZINTERNAL = 120 Ω
Ot2od Digital output, TTL-compatible, 2 mA, open drain, ZINTERNAL = 120 Ω
AGND Analog Ground
GND Digital Ground
SC56D Single Chip ACF Modem Data Sheet
3-22 Conexant 101098C
Table 3-8. CX20437 VC DC Electrical Characteristics
Parameter Symbol Min. Typ. Max. Units Test Conditions
Input Voltage Low VIN -0.30 – VDD+0.3 V
Input Voltage Low VIL -0.30 – VDD+0.3 V
Input Voltage High VIH 0.4*VDD – – V
Output Voltage Low VOL 0–0.4V
Output Voltage High VOH 0.8*VDD – VDD V
Input Leakage Current – -10 – 10 µA
Output Leakage Current (High Impedance) – -10 – 10 µA
Test conditions unless otherwise noted:
1. Test Conditions unless otherwise stated: VDD = +3.3 ± 0.3 VDC; TA = 0°C to 70°C; external load = 50 pF
Table 3-9. CX20437 VC Analog Electrical Characteristics
Signal Name Type Characteristic Value
M_LINE_IN, I (DA) Input Impedance > 70K Ω
M_MIC_IN AC Input Voltage Range 1.1 VP-P
Reference Voltage +1.35 VDC
M_LINE_OUTP O (DD) Minimum Load 300 Ω
Maximum Capacitive Load 0 µF
Output Impedance 10 Ω
AC Output Voltage Range 1.4 VP-P (with reference to ground and a 600 Ω load)
Reference Voltage +1.35 VDC
DC Offset Voltage ± 200 mV
M_SPKR_OUT O (DF) Minimum Load 300 Ω
Maximum Capacitive Load 0.01 µF
Output Impedance 10 Ω
AC Output Voltage Range 1.4 VP-P
Reference Voltage +1.35 VDC
DC Offset Voltage ± 20 mV
Test conditions unless otherwise noted:
1. Test Conditions unless otherwise stated: VDD = +3.3 ± 0.3 VDC; MAVDD = +3.3 ± 0.3 VDC, TA = 0°C to 70°C
Parameter Min Typ Max Units
DAC to Line Driver output (600Ω load, 3dB in SCF and CTF) SNR/SDR at:
4Vp-p differential
2Vp-p differential
-10dBm differential
88/85
82/95
72/100
dB
DAC to Speaker Driver output (150Ω load, 3dB in SCF and CTF, -6dB in speaker driver)
SNR/SDR at:
2Vp-p
1Vp-p
-10dBm
88/75
82/80
72/83
dB
Line Input to ADC (6dB in AAF) SNR/SDR at –10 dBm 80/95 dB
Input Leakage Current (analog inputs) -10 10 µA
Output Leakage Current (analog outputs) -10 10 µA
SC56D Single Chip ACF Modem Data Sheet
101098C Conexant 3-23
3.3 Electrical and Environmental Specifications
3.3.1 Operating Conditions, Absolute Maximum Ratings, and Power Requirements
The operating conditions are specified in Table 3-10.
The absolute maximum ratings are listed in Table 3-11.
The current and power requirements are listed in Table 3-12.
Table 3-10. Operating Conditions
Parameter Symbol Limits Units
Supply Voltage VDD +3.0 to +3.6 VDC
Operating Temperature Range TA0 to +70 °C
Table 3-11. Absolute Maximum Ratings
Parameter Symbol Limits Units
Supply Voltage VDD -0.5 to +4.0 VDC
Input Voltage VIN -0.5 to (VGG +0.5)* VDC
Storage Temperature Range TSTG -55 to +125 °C
Analog Inputs VIN -0.3 to (VAA + 0.5) VDC
Voltage Applied to Outputs in High Impedance (Off) State VHZ -0.5 to (VGG +0.5)* VDC
DC Input Clamp Current IIK ±20 mA
DC Output Clamp Current IOK ±20 mA
Static Discharge Voltage (25°C) VESD ±2500 VDC
Latch-up Current (25°C) ITRIG ±400 mA
* VGG = +3.3V ± 0.3V or +5V ± 5%.
Table 3-12. Current and Power Requirements
Mode
Typical
Current
(Ityp)
(mA)
Maximum
Current
(Imax)
(mA)
Typical
Power
(Ptyp)
(mW)
Maximum
Power
(Pmax)
(mW)
Notes
CX06827 SCFACF
Normal Mode: Off-hook, normal data connection 83 91 274 328 f = 28.224 MHz
Normal Mode: On-hook, idle, waiting for ring 83 91 274 328 f = 28.224 MHz
Sleep Mode 8.4 9.2 27.7 33.1 f = 0 MHz
CX20437 VC (Optional)
Normal Mode 1.5 2 5 7
Notes:
1. Operating voltage: VDD = +3.3V ± 0.3V.
2. Test conditions: VDD = +3.3V for typical values; VDD = +3.6V for maximum values.
3. Input Ripple
≤ 0.1 Vpeak-peak.
4. f = Internal frequency.
5. Maximum current computed from Ityp: Imax = Ityp * 1.1.
6. Typical power (Ptyp) computed from Ityp: Ptyp = Ityp * 3.3V; Maximum power (Pmax) computed from Imax: Pmax = Imax * 3.6V.
SC56D Single Chip ACF Modem Data Sheet
3-24 Conexant 101098C
3.3.2 Interface and Timing Waveforms
External Memory Bus Timing
The external memory bus timing is listed in Table 3-13 and illustrated in Figure 3-7.
Table 3-13. Timing - External Memory Bus
Symbol Parameter Min Typ. Max Units
tFI Internal Operating Frequency 28.224 MHz
tCYC Internal Operating Clock Cycle 35.43 ns
Read
tAS READ# High to Address Valid – 11.2 12.5 ns
tES READ# High to ES Valid – 12.2 13.5 ns
tRW READ# Pulse Width 17.72 124.01 ns
tRDS Read Data Valid to READ# High 6.1 – ns
tRDH READ# High to Read Data Hold 0 – ns
Write
tAS WRITE# High to Address Valid – 11.2 12.5 ns
tES WRITE# High to ES Valid – 12.2 13.5 ns
tWW WRITE# to WRITE# Pulse Width 17.72 124.01 ns
tWTD WRITE# Low to Write Data Valid – 7.1 8.0 ns
tWTH WRITE# High to Write Data Hold 5.0 – ns
Notes:
1. ES = RAMSEL# or ROMSEL#.
2. Read pulse width and write pulse width:
RAM: tRW, tWW = 0.5 tCYC = 17.72 for Non-Extended Cycle Timing
ROM: tRW, tWW = 3.5 tCYC = 124.01 for Extended Cycle Timing
3. Memory speed determination:
RAM: tACCESS = tCYC - tES - tRDS = 35.43 - 13.5 - 6.3 = 15.63 ns (i.e., use 15 ns memory)
ROM: tACCESS = 4(tCYC) - tES - tRDS = 4(35.43) - 13.5 - 6.3 = 121.92 ns (i.e., use 90 ns memory).
4. Output Enable to Output Delay Timing:
RAM: tOE = tRW - tRDS = 0.5(tCYC) - tRDS = 17.72 - 6.3 = 11.42 ns
ROM: tOE = tRW - tRDS = 3.5(tCYC) - tRDS = 124.01 - 6.3 = 117.71 ns.
SC56D Single Chip ACF Modem Data Sheet
101098C Conexant 3-25
Write Timing
Read Timing
tCYC
tAS
RDH
C2*
A[18:0]
tRW
tt
RDS
READ#
D[7:0]
ES#**
tES
* C2 = Internal Phase 2 clock.
** ES# = RAMSEL# or ROMSEL#.
100491 F3-09 WF EB
tCYC
tAS
tWW
ttWTH
WTD
ES
t
C2*
A[18:0]
WRITE#
D[7:0]
ES#**
* C2 = Internal Phase 2 clock.
** ES# = RAMSEL# or ROMSEL#.
Figure 3-7. Waveforms - External Memory Bus
SC56D Single Chip ACF Modem Data Sheet
3-26 Conexant 101098C
Parallel Host Bus Timing
The parallel host bus timing is listed in Table 3-14 and illustrated in Figure 3-8.
Table 3-14. Timing - Parallel Host Bus
Symbol Parameter Min Max Units
READ (See Notes 1, 2, 3, 4, 5, and 6)
tAS Address Setup 5 – ns
tAH Address Hold 10 – ns
tCS Chip Select Setup 0 – ns
tCH Chip Select Hold 10 – ns
tRD HRD# Strobe Width 51 – ns
tDD Read Data Delay – 45 ns
tDRH Read Data Hold 10 – ns
WRITE (See Notes 1, 2, 3, 4, 5, and 6)
tAS Address Setup 5 – ns
tAH Address Hold 10 – ns
tCS Chip Select Setup 0 – ns
tCH Chip Select Hold 10 – ns
tWT HWT# Strobe Width 50 – ns
tDS Write Data Setup (see Note 4) – 35 ns
tDWH Write Data Hold (see Note 5) 5 – ns
Notes:
1. When the host executes consecutive Rx FIFO reads, a minimum delay of 2 times the internal CPU clock cycle plus
15 ns (85.86 ns at 28.224 MHz) is required from the falling edge of HRD# to the falling edge of the next Host Rx
FIFO HRD# clock.
2. When the Host executes consecutive Tx FIFO writes, a minimum delay of 2 times the internal CPU clock cycle plus
15 ns (85.86 ns at 28.224 MHz) is required from the falling edge of HWT# to the falling edge of the next Host Tx
FIFO HWT# clock.
3. tRD, tWT = tCYC + 15 ns.
4. tDS is measured from the point at which both HCS# and HWT# are active.
5. tDWH is measured from the point at which either HCS# and HWT# become inactive.
6. Clock frequency = 28.224 MHz clock.
SC56D Single Chip ACF Modem Data Sheet
101098C Conexant 3-27
tAS tAH
tCS tCH
tRD
tDD tDRH
HA[2-0]
HCS#
HRD#
HWT#
HD[7-0]
tAS tAH
tCS tCH
HA[2-0]
tWT
tDS tDWH
HCS#
HRD#
HWT#
HD[7-0]
100491 F3-10 WF-HB
a. Host Read
b. Host Write
Figure 3-8. Waveforms - Parallel Host Bus
SC56D Single Chip ACF Modem Data Sheet
3-28 Conexant 101098C
Serial DTE Interface
The serial DTE interface waveforms for 4800 and 9600 bps are illustrated in Figure 3-9.
TXCLK
4800 BPS
TXD
4800 BPS
TXCLK
9600 BPS
TXD
9600 BPS
NOTE: THIS FIGURE IS VALID FOR SYNCHRONOUS MODE ONLY. THERE IS NO RELATIONSHIP BETWEEN
NOTE: TXD AND TXCLK IN ASYNCHRONOUS MODE.
RXCLK
4800 BPS
RXD
4800 BPS
RXCLK
9600 BPS
RXD
9600 BPS
NOTE: THIS FIGURE IS VALID FOR SYNCHRONOUS MODE ONLY. THERE IS NO RELATIONSHIP BETWEEN
NOTE: RXD AND RXCLK IN ASYNCHRONOUS MODE.
a. Transmit
b. Receive
1227F3-14 WF-Ser DTE
Figure 3-9. Waveforms - Serial DTE Interface
SC56D Single Chip ACF Modem Data Sheet
101098C Conexant 4-1
4 PACKAGE DIMENSIONS
The 144-pin TQFP package dimensions are shown in Figure 4-1.
The 32-pin TQFP package dimensions are shown in Figure 4-2.
eb
D
DETAIL A
DETAIL A
A1
L1
c
L
A
D2
D1 D1
A2
Millimeters
0.05
21.75
0.5
0.17
0.11
1.6 MAX
0.15
1.4 REF
22.25
20.0 REF
17.5 REF
0.75
1.0 REF
0.50 BSC
0.27
0.17
0.08 MAX
0.0020
0.8563
0.0197
0.0067
0.0043
A
A1
A2
D
D1
D2
L
L1
e
b
c
Coplanarity
Min. Max. Min. Max.
Inches*
Dim.
Ref: 144-PIN TQFP (GP00-D252)
* Metric values (millimeters) should be used for
PCB layout. English values (inches) are
converted from metric values and may include
round-off errors.
0.0630 MAX
0.0059
0.0551 REF
0.8760
0.7874 REF
0.6890 REF
0.0295
0.0394 REF
0.0197 BSC
0.0106
0.0067
0.0031 MAX
PD-TQFP-144 (040395)
D1
D
D2
D1
PIN 1
REF
Figure 4-1. Package Dimensions - 144-Pin TQFP
SC56D Single Chip ACF Modem Data Sheet
4-2 Conexant 101098C
DETAIL A
A1
L1
c
L
A
D1
A2
Millimeters
0.05
8.75
0.5
0.30
0.13
1.6 MAX
0.15
1.4 REF
9.25
7.0 REF
5.6 REF
0.75
1.0 REF
0.80 BSC
0.40
0.19
0.10 MAX
0.0020
0.3445
0.0197
0.0118
0.0051
A
A1
A2
D
D1
D2
L
L1
e
b
c
Coplanarity
Min. Max. Min. Max.
Inches*
Dim.
Ref: 32-PIN TQFP (GP00-D262)
* Metric values (millimeters) should be used for
PCB layout. English values (inches) are
converted from metric values and may include
round-off errors.
0.0630 MAX
0.0059
0.0551 REF
0.3642
0.2756 REF
0.2205 REF
0.0295
0.0394 REF
0.0315 BSC
0.0157
0.0075
0.004 MAX
PD-TQFP-32 (040395)
DETAIL A
D1
eb
DD2
D1
D1
D
D2
PIN 1
REF
Figure 4-2. Package Dimensions - 32-pin TQFP
SC56D Single Chip ACF Modem Data Sheet
101098C Conexant 5-1
5 PARALLEL HOST INTERFACE
The modem supports a 16550A interface in parallel interface versions. The 16550A interface can operate in FIFO mode or
non-FIFO mode. Non-FIFO mode is the same as 16450 interface operation. FIFO mode unique operations are identified.
5.1 Overview
The parallel interface registers and the corresponding bit assignments are shown in Table 5-1.
The modem emulates the 16450/16550A interface and includes both a 16-byte receiver data first-in first-out buffer (RX FIFO)
and a 16-byte transmit data first-in first-out buffer (TX FIFO). When FIFO mode is selected in the FIFO Control Register
(FCR0 = 1), both FIFOs are operative. Furthermore, when FIFO mode is selected, DMA operation of the FIFO can also be
selected (FCR3 = 1). When FIFO mode is not selected, operation is restricted to 16450 interface operation.
The received data is read by the host from the Receiver Buffer (RX Buffer). The RX Buffer corresponds to the Receiver Buffer
Register in a 16550A device. In FIFO mode, the RX FIFO operates transparently behind the RX Buffer. Interface operation is
described with reference to the RX Buffer in both FIFO and non-FIFO modes.
The transmit data is loaded by the host into the Transmit Buffer (TX Buffer). The TX Buffer corresponds to the Transmit
Holding Register in a 16550A device. In FIFO mode, the TX FIFO operates transparently behind the TX Buffer. Interface
operation is described with reference to the TX Buffer in both FIFO and non-FIFO modes.
SC56D Single Chip ACF Modem Data Sheet
5-2 Conexant 101098C
Table 5-1. Parallel Interface Registers
Register Register Bit No.
No. Name 7654321 0
7 Scratch Register (SCR) Scratch Register
6 Modem Status Register
(MSR)
Data
Carrier
Detect
(DCD)
Ring
Indicator
(RI)
Data Set
Ready
(DSR)
Clear to
Send
(CTS)
Delta Data
Carrier
Detect
(DDCD)
Trailing
Edge of
Ring
Indicator
(TERI)
Delta Data
Set Ready
(DDSR)
Delta Clear
to Send
(DCTS)
5 Line Status Register (LSR) RX FIFO
Error
Transmitter
Empty
(TEMT)
Transmitter
Buffer
Register
Empty
(THRE)
Break
Interrupt
(BI)
Framing
Error
(FE)
Parity
Error
(PE)
Overrun
Error
(OE)
Receiver
Data
Ready
(DR)
4 Modem Control Register
(MCR)
0 0 0 Local
Loopback
Out 2 Out 1 Request to
Send
(RTS)
Data
Terminal
Ready
(DTR)
3 Line Control Register
(LCR)
Divisor
Latch
Access Bit
(DLAB)
Set Break Stick Parity Even Parity
Select
(EPS)
Parity
Enable
(PEN)
Number of
Stop Bits
(STB)
Word
Length
Select Bit 1
(WLS1)
Word
Length
Select Bit 0
(WLS0)
2 Interrupt Identify Register
(IIR) (Read Only)
FIFOs
Enabled
FIFOs
Enabled
0 0 Pending
Interrupt ID
Bit 2
Pending
Interrupt ID
Bit 1
Pending
Interrupt ID
Bit 0
“0" if
Interrupt
Pending
2 FIFO Control Register
(FCR) (Write Only)
Receiver
Trigger
MSB
Receiver
Trigger
LSB
Reserved Reserved DMA Mode
Select
TX FIFO
Reset
RX FIFO
Reset
FIFO
Enable
1
(DLAB = 0)
Interrupt Enable Register
(IER)
0 0 0 0 Enable
Modem
Status
Interrupt
(EDSSI)
Enable
Receiver
Line Status
Interrupt
(ELSI)
Enable
Transmitter
Holding
Register
Empty
Interrupt
(ETBEI)
Enable
Received
Data
Available
Interrupt
(ERBFI)
0
(DLAB = 0)
Transmitter Buffer
Register (THR)
Transmitter FIFO Buffer Register (Write Only)
0
(DLAB = 0)
Receiver Buffer Register
(RBR)
Receiver FIFO Buffer Register (Read Only)
1
(DLAB = 1)
Divisor Latch MSB
Register (DLM)
Divisor Latch MSB
0
(DLAB = 1)
Divisor Latch LSB Register
(DLL)
Divisor Latch LSB
SC56D Single Chip ACF Modem Data Sheet
101098C Conexant 5-3
5.2 Register Signal Definitions
5.2.1 IER - Interrupt Enable Register (Addr = 1, DLAB = 0)
The IER enables five types of interrupts that can separately assert the HINT output signal (Table 5-2). A selected interrupt
can be enabled by setting the corresponding enable bit to a 1, or disabled by setting the corresponding enable bit to a 0.
Disabling an interrupt in the IER prohibits setting the corresponding indication in the IIR and assertion of HINT. Disabling all
interrupts (resetting IER0 - IER3 to a 0) inhibits setting of any Interrupt Identifier Register (IIR) bits and inhibits assertion of the
HINT output. All other system functions operate normally, including the setting of the Line Status Register (LSR) and the
Modem Status Register (MSR).
Bits 7-4 Not used.
Always 0.
Bit 3 Enable Modem Status Interrupt (EDSSI).
This bit, when a 1, enables assertion of the HINT output whenever the Delta CTS (MSR0), Delta DSR (MSR1),
Delta TER (MSR2), or Delta DCD (MSR3) bit in the Modem Status Register (MSR) is a 1. This bit, when a 0,
disables assertion of HINT due to setting of any of these four MSR bits.
Bit 2 Enable Receiver Line Status Interrupt (ELSI).
This bit, when a 1, enables assertion of the HINT output whenever the Overrun Error (LSR1), Parity Error
(LSR2), Framing Error (LSR3), or Break Interrupt (LSR4) receiver status bit in the Line Status Register (LSR)
changes state. This bit, when a 0, disables assertion of HINT due to change of the receiver LSR bits 1-4.
Bit 1 Enable Transmitter Holding Register Empty Interrupt (ETBEI).
This bit, when a 1, enables assertion of the HINT output when the Transmitter Empty bit in the Line Status
Register (LSR5) is a 1. This bit, when a 0, disables assertion of HINT due to LSR5.
Bit 0 Enable Receiver Data Available Interrupt (ERBFI) and Character Timeout in FIFO Mode.
This bit, when a 1, enables assertion of the HINT output when the Receiver Data Ready bit in the Line Status
Register (LSR0) is a1 or character timeout occurs in the FIFO mode. This bit, when a 0, disables assertion of
HINT due to the LSR0 or character timeout.
SC56D Single Chip ACF Modem Data Sheet
5-4 Conexant 101098C
5.2.2 FCR - FIFO Control Register (Addr = 2, Write Only)
The FCR is a write-only register used to enable FIFO mode, clear the RX FIFO and TX FIFO, enable DMA mode, and set the
RX FIFO trigger level.
Bits 7-6 RX FIFO Trigger Level.
FCR7 and FCR6 set the trigger level for the RX FIFO (Receiver Data Available) interrupt.
FCR7 FCR6 RX FIFO Trigger Level (Bytes)
00 01
01 04
10 08
11 14
Bits 5-4 Not used.
Bit 3 DMA Mode Select.
When FIFO mode is selected (FCR0 = 1), FCR3 selects non-DMA operation (FCR3 = 0) or DMA operation
(FCR3 = 1). When FIFO mode is not selected (FCR0 = 0), this bit is not used (the modem operates in non-
DMA mode in 16450 operation).
DMA operation in FIFO mode.
RXRDY will be asserted when the number of characters in the RX FIFO is equal to or greater than the value in
the RX FIFO Trigger Level (IIR0-IIR3 = 4h) or the received character timeout (IIR0-IIR3 = Ch) has occurred.
RXRDY will go inactive when there are no more characters in the RX FIFO.
TXRDY will be asserted when there are one or more empty (unfilled) locations in the TX FIFO. TXRDY will go
inactive when the TX FIFO is completely full.
Non-DMA operation in FIFO mode.
RXRDY will be asserted when there are one or more characters in the RX FIFO. RXRDY will go inactive when
there are no more characters in the RX FIFO.
TXRDY will be asserted when there are no characters in the TX FIFO. TXRDY will go inactive when the first
character is loaded into the TX FIFO Buffer.
Bit 2 TX FIFO Reset.
When FCR2 is a 1, all bytes in the TX FIFO are cleared. This bit is cleared automatically by the modem.
Bit 1 RX FIFO Reset.
When FCR1 is a 1, all bytes in the RX FIFO are cleared. This bit is cleared automatically by the modem.
Bit 0 FIFO Enable.
When FCR0 is a 0, 16450 mode is selected and all bits are cleared in both FIFOs. When FCR0 is a 1, FIFO
mode (16550A mode) is selected and both FIFOs are enabled. FCR0 must be a 1 when other bits in the FCR
are written or they will not be acted upon.
SC56D Single Chip ACF Modem Data Sheet
101098C Conexant 5-5
5.2.3 IIR - Interrupt Identifier Register (Addr = 2)
The Interrupt Identifier Register (IIR) identifies the existence and type of up to five prioritized pending interrupts. Four priority
levels are set to assist interrupt processing in the host. The four levels, in order of decreasing priority, are: Highest: Receiver
Line Status, 2: Receiver Data Available or Receiver Character Timeout, 3: TX Buffer Empty, and 4: Modem Status.
When the IIR is accessed, the modem freezes all interrupts and indicates the highest priority interrupt pending to the host.
Any change occurring in interrupt conditions are not indicated until this access is complete.
Bits 7-6 FIFO Mode.
These two bits copy FCR0.
Bits 5-4 Not Used.
Always 0.
Bits 3-1 Highest Priority Pending Interrupt.
These three bits identify the highest priority pending interrupt (Table 5-2). Bit 3 is applicable only when FIFO
mode is selected, otherwise bit 3 is a 0.
Bit 0 Interrupt Pending.
When this bit is a 0, an interrupt is pending; IIR bits 1-3 can be used to determine the source of the interrupt.
When this bit is a1, an interrupt is not pending.
Table 5-2. Interrupt Sources and Reset Control
Interrupt Identification Register Interrupt Set and Reset Functions
Bit 3
(Note 1)
Bit 2 Bit 1 Bit 0 Priority
Level
Interrupt Type Interrupt Source Interrupt Reset Control
0 0 0 1 — None None —
0 1 1 0 Highest Receiver Line
Status
Overrun Error OE (LSR1),
Parity Error (PE) (LSR2),
Framing Error (FE) (LSR3),
or Break Interrupt (BI) (LSR4)
Reading the LSR
0 1 0 0 2 Received Data
Available
Received Data Available (LSR0) or RX
FIFO Trigger Level (FCR6-FCR7)
Reached1
Reading the RX Buffer or
the RX FIFO drops below
the Trigger Level
1 1 0 0 2 Character Time-
out Indication 1
The RX FIFO contains at least 1
character and no characters have been
removed from or input to the RX FIFO
during the last 4 character times.
Reading the RX Buffer
0 0 1 0 3 TX Buffer Empty TX Buffer Empty Reading the IIR or writing
to the TX Buffer
0 0 0 0 4 Modem Status Delta CTS (DCTS) (MSR0),
Delta DSR (DDSR) (MSR1),
Trailing Edge Ring Indicator (TERI)
(MSR3), or Delta DCD (DCD) (MSR4)
Reading the MSR
Notes:
1. FIFO Mode only.
SC56D Single Chip ACF Modem Data Sheet
5-6 Conexant 101098C
5.2.4 LCR - Line Control Register (Addr = 3)
The Line Control Register (LCR) specifies the format of the asynchronous data communications exchange.
Bit 7 Divisor Latch Access Bit (DLAB).
This bit must be set to a 1 to access the Divisor latch registers during a read or write operation. It must be
reset to a 0 to access the Receiver Buffer, the Transmitter Buffer, or the Interrupt Enable Register.
Bit 6 Set Break.
When bit 6 is a 1, the transmit data is forced to the break condition, i.e., space (0) is sent. When bit 6 is a 0,
break is not sent. The Set Break bit acts only on the transmit data and has no effect on the serial in logic.
Bit 5 Stick Parity.
When parity is enabled (LCR3 = 1) and stick parity is selected (LCR5 = 1), the parity bit is transmitted and
checked by the receiver as a 0 if even parity is selected (LCR4 = 1) or as a 1 if odd parity is selected (LCR4 =
0). When stick parity is not selected (LCR3 = 0), parity is transmit and checked as determined by the LCR3
and LCR4 bits.
Bit 4 Even Parity Select (EPS).
When parity is enabled (LCR3 = 1) and stick parity is not selected (LCR5 = 0), the number of 1s transmitted or
checked by the receiver in the data word bits and parity bit is either even (LCR4 = 1) or odd (LCR4 = 0).
Bit 3 Enable Parity (PEN).
When bit 3 is a 1, a parity bit is generated in the serial out (transmit) data stream and checked in the serial in
(receive) data stream as determined by the LCR 4 and LCR5 bits. The parity bit is located between the last
data bit and the first stop bit.
Bit 2 Number of Stop Bits (STB).
This bit specifies the number of stop bits in each serial out character. If bit 2 is a 0, one stop bit is generated
regardless of word length. If bit 2 is a 1 and 5-bit word length is selected, one and one-half stop bits are
generated. If bit 2 is a 1 and a 6-, 7-, or 8-bit word length is selected, two stop bits are generated. The serial in
logic checks the first stop bit only, regardless of the number of stop bits selected.
Bits 1-0 Word Length Select (WLS0 and WLS1).
These two bits specify the number of bits in each serial in or serial out character. The encoding of bits 0 and 1
is:
Bit 1 Bit 0 Word Length
0 0 5 Bits (Not supported)
0 1 6 Bits (Not supported)
10 7 Bits
11 8 Bits
SC56D Single Chip ACF Modem Data Sheet
101098C Conexant 5-7
5.2.5 MCR - Modem Control Register (Addr = 4)
The Modem Control Register (MCR) controls the interface with the modem or data set.
Bit 7-5 Not used.
Always 0.
Bit 4 Local Loopback.
When this bit is set to a 1, the diagnostic mode is selected and the following occurs:
1. Data written to the Transmit Buffer is looped back to the Receiver Buffer.
2. The DTS (MCR0), RTS (MCR1), Out1 (MCR2), and Out2 (MCR3) modem control register bits are
internally connected to the DSR (MSR5), CTS (MSR4), RI (MSR6), and DCD (MSR7) modem status
register bits, respectively.
Bit 3 Output 2.
When this bit is a 1, HINT is enabled. When this bit is a 0, HINT is in the high impedance state.
Bit 2 Output 1.
This bit is used in local loopback (see MCR4).
Bit 1 Request to Send (RTS).
This bit controls the Request to Send (RTS) function. When this bit is a 1, RTS is on. When this bit is a 0, RTS
is off.
Bit 0 Data Terminal Ready (DTR).
This bit controls the Data Terminal Ready (DTR) function. When this bit is a 1, DTR is on. When this bit is a 0,
DTR is off.
SC56D Single Chip ACF Modem Data Sheet
5-8 Conexant 101098C
5.2.6 LSR - Line Status Register (Addr = 5)
This 8-bit register provides status information to the host concerning data transfer.
Bit 7 RX FIFO Error.
In the 16450 mode, this bit is not used and is always 0.
In the FIFO mode, this bit is set if there are one or more characters in the RX FIFO with a parity error, framing
error, or break indication detected. This bit is reset to a 0 when the host reads the LSR and none of the above
conditions exist in the RX FIFO.
Bit 6 Transmitter Empty (TEMT).
This bit is set to a 1 whenever the TX Buffer (THR) and equivalent of the Transmitter Shift Register (TSR) are
both empty. It is reset to a 0 whenever either the THR or the equivalent of the TSR contains a character.
In the FIFO mode, this bit is set to a 1 when ever the TX FIFO and the equivalent of the TSR are both empty.
Bit 5 Transmitter Holding Register Empty (THRE) [TX Buffer Empty].
This bit, when set, indicates that the TX Buffer is empty and the modem can accept a new character for
transmission. In addition, this bit causes the modem to issue an interrupt to the host when the Transmit
Holding Register Empty Interrupt Enable bit (IIR1) is set to 1. The THRE bit is set to a 1 when a character is
transferred from the TX Buffer. The bit is reset to 0 when a byte is written into the TX Buffer by the host.
In the FIFO mode, this bit is set when the TX FIFO is empty; it is cleared when at least one byte is in the TX
FIFO.
Bit 4 Break Interrupt (BI).
This bit is set to a 1 whenever the received data input is a space (logic 0) for longer than two full word lengths
plus 3 bits. The BI bit is reset when the host reads the LSR.
Bit 3 Framing Error (FE).
This bit indicates that the received character did not have a valid stop bit. The FE bit is set to a 1 whenever
the stop bit following the last data bit or parity bit is detected as a logic o (space). The FE bit is reset to a 0
when the host reads the LSR.
In the FIFO mode, the error indication is associated with the particular character in the FIFO it applies to; the
FE bit is set to a 1 when this character is loaded into the RX Buffer.
Bit 2 Parity Error (PE).
This bit indicates that the received data character in the RX Buffer does not have the correct even or odd
parity, as selected by the Even Parity Select bit (LCR4) and the Stick Parity bit (LCR5). The PE bit is reset to a
0 when the host reads the LSR.
In the FIFO mode, the error indication is associated with the particular character in the it applies to; the PE bit
is set to a 1 when this character is loaded into the RX Buffer.
Bit 1 Overrun Error (OE).
This bit is set to a 1 whenever received data is loaded into the RX Buffer before the host has read the
previous data from the RX Buffer. The OE bit is reset to a 0 when the host reads the LSR.
In the FIFO mode, if data continues to fill beyond the trigger level, an overrun condition will occur only if the
RX FIFO is full and the next character has been completely received.
Bit 0 Receiver Data Ready (DR).
This bit is set to a 1 whenever a complete incoming character has been received and has been transferred
into the RX Buffer. The DR bit is reset to a 0 when the host reads the RX Buffer.
In the FIFO mode, the DR bit is set when the number of received data bytes in the RX FIFO equals or
exceeds the trigger level specified in FCR0-FCR1.
SC56D Single Chip ACF Modem Data Sheet
101098C Conexant 5-9
5.2.7 MSR - Modem Status Register (Addr = 6)
The Modem Status Register (MSR) reports current state and change information of the modem. Bits 4-7 supply current state
and bits 0-3 supply change information. The change bits are set to a 1 whenever a control input from the modem changes
state from the last MSR read by the host. Bits 0-3 are reset to 0 when the host reads the MSR or upon reset.
Whenever bits 0, 1, 2, or 3 are set to a 1, a Modem Status Interrupt (IIR0-IIR3 = 0) is generated.
Bit 7 Data Carrier Detect (DCD).
This bit indicates the logic state of the DCD# (RLSD#) output. If Loopback is selected (MCR4 = 1), this bit
reflects the state of the Out2 bit in the MCR (MCR3).
Bit 6 Ring Indicator (RI).
This bit indicates the logic state of the RI# output. If Loopback is selected (MCR4 = 1), this bit reflects the
state of the Out1 bit in the MCR (MCR2).
Bit 5 Data Set Ready (DSR).
This bit indicates the logic state of the DSR# output. If Loopback is selected (MCR4 = 1), this bit reflects the
state of the DTR bit in the MCR (MCR0).
Bit 4 Clear to Send (CTS).
This bit indicates the logic state of the CTS# output. If Loopback is selected (MCR4 = 1), this bit reflects the
state of the RTS bit in the MCR (MCR1).
Bit 3 Delta Data Carrier Detect (DDCD).
This bit is set to a 1 when the DCD bit changes state since the MSR was last read by the host.
Bit 2 Trailing Edge of Ring Indicator (TERI).
This bit is set to a 1 when the RI bit changes from a 1 to a 0 state since the MSR was last read by the host.
Bit 1 Delta Data Set Ready (DDSR).
This bit is set to a 1 when the DSR bit has changed since the MSR was last read by the host.
Bit 0 Delta Clear to Send (DCTS).
This bit is set to a 1 when the CTS bit has changed since the MSR was last read by the host.
5.2.8 RBR - RX Buffer (Receiver Buffer Register) (Addr = 0, DLAB = 0)
The RX Buffer (RBR) is a read-only register at location 0 (with DLAB = 0). Bit 0 is the least significant bit of the data, and is
the first bit received.
5.2.9 THR - TX Buffer (Transmitter Holding Register) (Addr = 0, DLAB = 0)
The TX Buffer (THR) is a write-only register at address 0 when DLAB = 0. Bit 0 is the least significant bit and the first bit sent.
5.2.10 Divisor Registers (Addr = 0 and 1, DLAB = 1)
The Divisor Latch LS (least significant byte) and Divisor Latch MS (most significant byte) are two read-write registers at
locations 0 and 1 when DLAB = 1, respectively.
The baud rate is selected by loading each divisor latch with the appropriate hex value.
Programmable values corresponding to the desired baud rate are listed in Table 5-3.
5.2.11 SCR - Scratch Register (Addr = 7)
The Scratchpad Register is a read-write register at location 7. This register is not used by the modem and can be used by the
host for temporary storage.
SC56D Single Chip ACF Modem Data Sheet
5-10 Conexant 101098C
Table 5-3. Programmable Baud Rates
Divisor Latch (Hex)
MS LS Divisor (Decimal) Baud Rate
06 00 1536 75
04 17 1047 110
03 00 768 150
01 80 384 300
00 C0 192 600
00 60 96 1200
00 30 48 2400
00 18 24 4800
00 0C 12 9600
00 06 6 19200
00 04 4 28800
00 03 3 38400
00 02 2 57600
00 01 1 115200
00 00 NA 230400
5.3 Receiver FIFO Interrupt Operation
5.3.1 Receiver Data Available Interrupt
When the FIFO mode is enabled (FCR0 = 1) and receiver interrupt (RX Data Available) is enabled (IER0 = 1), receiver
interrupt operation is as follows:
1. The Receiver Data Available Flag (LSR0) is set as soon as a received data character is available in the RX FIFO. LSR0
is cleared when the RX FIFO is empty.
2. The Receiver Data Available interrupt code (IIR0-IIR4 = 4h) is set whenever the number of received data bytes in the RX
FIFO reaches the trigger level specified by FCR6-FCR7 bits; it is cleared whenever the number of received data bytes in
the RX FIFO drops below the trigger level specified by FCR6-FCR7 bits.
3. The HINT interrupt is asserted whenever the number of received data bytes in the RX FIFO reaches the trigger level
specified by FCR6-FCR7 bits. HINT interrupt is de-asserted when the number of received data bytes in the RX FIFO
drops below the trigger level specified by FCR6-FCR7 bits.
5.3.2 Receiver Character Timeout Interrupts
When the FIFO mode is enabled (FCR0 = 1) and receiver interrupt (Receiver Data Available) is enabled (IER0 = 1), receiver
character timeout interrupt operation is as follows:
1. A Receiver character timeout interrupt code (IIR0-IIR3 = Ch) is set if at least one received character is in the RX FIFO,
the most recent received serial character was longer than four continuous character times ago (if 2 stop bits are
specified, the second stop bit is included in this time period), and the most recent host read of the RX FIFO was longer
than four continuous character times ago.
5.4 Transmitter FIFO Interrupt Operation
5.4.1 Transmitter Empty Interrupt
When the FIFO mode is enabled (FCR0 = 1) and transmitter interrupt (TX Buffer Empty) is enabled (IER0 = 1), transmitter
interrupt operation is as follows:
1. The TX Buffer Empty interrupt code (IIR0-IIR3 = 2h) will occur when the TX Buffer is empty; it is cleared when the TX
Buffer is written to (1 to 16 characters) or the IIR is read.
2. The TX Buffer Empty indications will be delayed 1 character time minus the last stop bit time whenever the following
occur: THRE = 1 and there have not been at least two bytes at the same time in the TX FIFO Buffer since the last setting
of THRE was set. The first transmitter interrupt after setting FCR0 will be immediate.
NOTES
Further Information
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