Oki 3320, 3321 specifications Mpu, Ras, Cas, CS1~CS4, Wrh Wrl

(3)RAM (MSM51C464A-80RS)

The RAM is CMOS dynamic RAM with (64K × 4-bit) × 2 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		A0~A7	RAM 1 (Q3)
			RAM 2 (Q4)
P03			RAS
CS1		D0~D3	CAS
			D4~D7
RD			OE
Clockout*	T1	T2	T3

A0~A7

CS1~CS4

RD

D0~D7

(Read)

WRH

WRL

D0~D7

(Write)

8-bit bus, byte instruction

* Clockout is provided when the original excitation is selected.

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