M16C62_M Datasheet, PDF (548/615 Pages) Renesas Technology Corp – 16-BIT SINGLE-CHIP MICROCOMPUTER M16C FAMILY / M16C/60 SERIES

External Buses
Mitsubishi microcomputers
M16C / 62A Group
SINGLE-CHIP 16-BIT CMOS MICROCOMPUTER
4.3.5 Chip Selects and Address Bus
When there are insufficient chip select signals, it is necessary to generate chip selects externally. Figure
________
4.3.6 shows an example of a connection in which the CS2 (128K bytes) area is divided into four 32K byte
areas.
Microcomputer
CNVSS
BYTE
WR
RD
A0 to A17
CS2
D0 to D7
A15 ₁
A16
2
A17
3
4
5
6
16
Y1
14
Y2
13
Y3
12
Y4
11
8
74HC138
IC0
A9 ₁
A8
2
A7
3
A6
4
A5
5
A4
6
A3
7
A2
8
A1
9
A0
10
D0 ₁₁
D1 ₁₂
D2 ₁₃
14
28
27
A10
26
A11
25
A12
24
A13
23
22
A14
21
Y1
20
D7
19
18 ^D6
17 ^D5
16 ^D4
D3
15
M5M5278
Memory map
0000016
0800016
IC0
0FFFF16
1000016
IC1
17FFF16
1800016
IC2
1FFFF16
2000016
IC3
2FFFF16
3000016
FFFFF16
CS2
Figure 4.3.6. Chip selects and address bus
IC3
A0 to A14
.....
Y4
D0 to D7
M5M5278
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