MT42C4256C-10/883C AUSTIN [Austin Semiconductor], MT42C4256C-10/883C Datasheet - Page 28

• Manufacturer Part Number: MT42C4256C-10/883C
• Description: 256K X 4 VRAM 256K x 4 DRAM with 512K x 4 SAM
• Manufacturer: AUSTIN [Austin Semiconductor]

NOTES:
1. Referenced to CAS or W, whichever occurs last
NOTE B: A read cycle or a read-modify-write cycle can be intermixed with write cycles, observing read and read-modify-write timing specifications.
TRG\ must remain high throughout the entire page-mode operation to assure page-mode cycle time if the late-write feature is used. If the early-write-
cycle timing is used, the state of TRG\ is a don’t care after the minimum period t
WRITE-CYCLE STATE TABLE
SMJ44C251B/MT42C4256
Rev. 0.1 12/03
Write Operation
Write-mask load/use, Write DQs to I/Os
Use previous write mask, Write DQs to I/Os
Load write mask on later of W\ fall and CAS\ fall
FIGURE 18: Enhanced-Page-Mode Write-Cycle Timing
Austin Semiconductor, Inc.
CYCLE
H
H
1
L
L
28
h(TRG)
2
L
L
L
L
Austin Semiconductor, Inc. reserves the right to change products or specifications without notice.
from the falling edge of RAS\.
STATE
H
H
3
L
L
Write Mask Valid Data
Don't Care
Don't Care
Don't Care Write Mask
4
SMJ44C251B
MT42C4256
Valid Data
Valid Data
VRAM
VRAM
VRAM
VRAM
VRAM
5