Oki PACEMARK 4410 Service Manual page 15

(3) DRAM(IC28)
The RAM is CMOS dynamic RAM with (256K x 16 bit) configuration, and used as buffers (such
as receiving buffer, printing buffer, DLL buffer and working buffer).
The following shows the examples of the memory access operation.
MPU
ALE
RD
WR
CS
CLK
MPU CLOCK
ALE
A16~BHE
AD0~AD15
RD
AD0~AD15
WR
CS
NHDC LSI
A16~BHE
AD0~AD15
A16~BHE
A0–A15
A0–A15
Figure 2.3
DRAMA0~A9
DRAMD0~D15
RAS
CASU
CASL
RD
WR
D0–D15
D0–D15
DRAM
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