FEDS81V04160A-01
1
Semiconductor MS81V04160A
10/24
OPERATION MODE
Write Operation Cycle (MODE2 = VSS)
The write operation is controlled by seven control signals, SWCK, RSTW1, RSTW2, WE1, WE2 and IE1, IE2.
Port1 write operation is accomplished by cycling SWCK, and holding WE1 and IE1 high after the write address
pointer reset operation or RSTW1. RSTW1 must be preformed for internal circuit initialization before Write
operation.
Each write operation, which begins after RSTW1, must contain at least 140 active write cycles, i.e . SWCK cycles
while WE1 a n d IE1 are hi gh. To tran sfe r the last data to the DRAM array, which at that time is stored in the serial
data registers attached to the DRAM array, an RSTW1 operation is required after the last SWCK cycle.
Note that every write timing of MS81V04160A is delayed by one clock compared with read timings for easy
cascading without any interface delay devices.
Setting MODE1 to the VSS level starts write data accessing in the cycle in which RSTW1, WE1, and IE1 control
signals are input.
Setting MODE1 to the VCC level starts write data accessing in t he cycle subse quent t o the cycle in whic h RSTW1,
WE1, and IE1 control signals are input.
These operation are the same for Port1 and Port2.
Settings of WE1, 2 and IE1, 2 to the operation mode of Write address pointer and Data input.
WE1, 2 IE1, 2 Internal Write address pointer Data input
H H Input
H L Incremented
L X Halted Not input
X indicates “don’t care”
Write Operation Cycle (MODE2=VCC)
The write operation is controlled by seven control signals, SWCK, RSTW1, RSTW2, WE1, WE2, and IE1, IE2.
Port1 write operation is accomplished by cycling SWCK and holding WE1 and IE1 low after the write address
pointer reset operation or RSTW1. RSTW1 must be performed for internal circuit initialization before write
operation.
Each write operation, which begins after RSTW1, must contain at least 140 active write cycle, i.e. SWCK cycles
while WE1 a n d IE1 are hi gh. To tran sfe r the last data to the DRAM array, which at that time is stored in the serial
data registers attached to the DRAM array, an RSTW1 operation is required after the last SWCK cycle.
Note that every write timing of MS8104160A is delayed by one clock compared with read timings for easy
cascading without any interface delay devices.
Setting MODE1 to the VSS level starts write data accessing in the cycle in which RSTW1.WE1, and IE1 control
signals are input.
Setting MODE1 to the VCC level starts write data accessing in the cycle in which RSTW1, WE1, and IE1 control
signals are input.
Setting MODE1 to the VCC level starts write data accessing in t he cycle subse quent t o the cycle in whic h RSTW1,
WE1, and IE1 control signals are input.
These operations are the same for port1 and Port2.