EM636327Q-7 Etron Technology Inc., EM636327Q-7 Datasheet - Page 12

• Manufacturer Part Number: EM636327Q-7
• Description: 512K x 32 High Speed Synchronous Graphics DRAM(SGRAM)
• Manufacturer: Etron Technology Inc.

Preliminary
registered coincident with the Block Write command is used to mask specific column/byte
combinations within the block. The mapping of the DQ inputs to the column/byte combinations is
shown in following table.
and the column/byte mask information, as shown in the following figure. The DQM and Mask
register masking operates normally as for a Write command, with the exception that the mask
information is applied simultaneously to all eight columns. Therefore, in a Block Write, a given bit is
written only if a "0" is registered for the corresponding DQM input, a "1" is registered for the
corresponding DQ signal, and the corresponding bit in the Mask register is "1".
The overall Block Write mask consists of a combination of the DQM inputs, the Mask register,
from corresponding
(previously loaded
Mask Register
Note: Only the lower byte is shown. The operation is identical for other bytes.
coincident with BankActivate
DQ inputs)
(selected by A0-A9,
BankActivate
and BS registered
command
Row in Bank
Command)
Write Command
Column Mask
DSF
Block-Write Masking Block Diagram
(registered
with Block
coincident
on the DQ
MR0
MR 1
MR2
MR3
MR4
MR5
MR6
MR7
D
CK
inputs
Q
DQM0
DQ0
DQ1
DQ2
DQ3
DQ4
DQ5
DQ6
DQ7
coincident with Block Write command)
12
(selected by A3-A7 registered
Block of Columns
EM636327
December
1998