M16C62_M Datasheet, PDF (48/615 Pages) Renesas Technology Corp – 16-BIT SINGLE-CHIP MICROCOMPUTER M16C FAMILY / M16C/60 SERIES

Bus Control
Mitsubishi microcomputers
M16C / 62A Group
SINGLE-CHIP 16-BIT CMOS MICROCOMPUTER
Table 1.9.2. External areas specified by the chip select signals
(A product having an internal RAM of more than 15K bytes and a ROM of more than 192K bytes)
Processor mode
CS0
Memory expansion mode
When PM13=0
3000016 to CFFFF16
(640K bytes)
When PM13=1
3000016 to BFFFF16
(576K bytes)
Microprocessor mode
0300016 to FFFFF16
(816K bytes)
Chip select signal
CS1
CS2
2800016 to
2FFFF16
(32K bytes)
0800016 to
27FFF16
(128K bytes)
CS3
When PM13=0
0400016 to
07FFF16
(16K bytes)
When PM13=1
0600016 to
07FFF16
(8K bytes)
Chip select control register
b7 b6 b5 b4 b3 b2 b1 b0
Symbol
CSR
Address
000816
When reset
0116
Bit symbol
CS0
CS1
CS2
CS3
CS0W
CS1W
CS2W
CS3W
Bit name
CS0 output enable bit
CS1 output enable bit
CS2 output enable bit
CS3 output enable bit
CS0 wait bit
CS1 wait bit
CS2 wait bit
CS3 wait bit
Function
RW
0 : Chip select output disabled
(Normal port pin)
1 : Chip select output enabled
0 : Wait state inserted
1 : No wait state
Figure 1.9.1. Chip select control register
The timing of the chip select signal changing to “L”(active) is synchronized with the address bus. But the
timing of the chip select signal changing to “H” depends on the area which will be accessed in the next
cycle. Figure 1.9.2 shows the output example of the address bus and chip select signal.
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