Casio CE-250 Service Manual

— 12 —
5-7. RAM / ROM bank selection circuit
This circuit is used for address decoder for memory.
Memory Map
C000
A000
8000
6000
4000
2000
0000
RAM BANK select
area (4 K)
E000
RAM common area
(8 K)
EP ROM
Common (16 K)
Mask ROM
(16 K)
F800
Internal RAM
(High speed access)
288 bytes
Internal RAM
(High speed access)
Short direct area
192 bytes
FE20
FFFF
FA80
Internal RAM
(High speed access)
Outer I/O area
F000
General purpose
register 32 bytes
Special function
register (SFR)
256 bytes
FEE0
FFF0
Bank
0
Bank
5
Bank
4
Bank
2
Bank
1
Bank
3
EP ROM
Bank select area
(16 K)
FAE0
FD00
Buffer RAM 32 bytes
FAC0
KI signal port (F800,F801)
000000
00001
00010
00011
00100
00101
00110
Bank
29
11101
RAM 256 K
RAM 1 M

Casio CE-250 Specifications

General

Brand	Casio
Model	CE-250
Category	Cash Register
Language	English