42089201TH Rev.4 12 /
Oki Data CONFIDENTIAL
(3) RAM
The RAM is CMOS dynamic RAM with 256K × 16bits (4Mbit), 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.
A0~A7
CAS-N UCAS-N
LCAS-N
WE-N
WRH-N
WRL-N
RAMMPU
P03
P04
CS1
WRL
P11
RD OE
D0~D15
RAS
UCAS
LCAS
WE
T1 T2 T3Clockout*
A0~A7
LGAS
RD
D0~D15
(Read)
WE
D0~D15
(Write)
16-bit bus, byte instruction
LS139
ALS11
* Clockout is provided when the original excitation is selected.