Oki PACEMARK 4410 - Page 15

40496501TH Rev.1 15
Figure 2.3
(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 CLOCK
ALE
A16~BHE
AD0~AD15
RD
AD0~AD15
WR
CS
AD0~AD15
A16~BHE
DRAMD0~D15
DRAMA0~A9
MPU NHDC LSI
DRAM
A16~BHE
A0–A15 D0–D15
A0–A15 D0–D15
ALE
RD
WR
CS
CLK
RAS
CASU
CASL
RD
WR