Oki 3391 Printer User Manual


 
2 – 5
(4) CG ROM
This is a 1024K × 16 bits (16M bits) MASK ROM with the font data for the characters
stored.
CG ROM is assigned to the program memory area of the MPU and is fetched by the PSEN
signal of the MPU.
The following shows the memory access operation.
D0~D15
P02
PSEN
MPU
CG-N
A0~A19
ROM
Program
IN
Program
IN
Program
IN
MPU CLOCK
A0~A19
CG-N
PSEN-N
D0~D15
CE
OE