M16C30_02 Datasheet, PDF (28/178 Pages) Renesas Technology Corp – SINGLE-CHIP 16-BIT CMOS MICROCOMPUTER

Bus Control
Mitsubishi microcomputers
M16C / 30 Group
SINGLE-CHIP 16-BIT CMOS MICROCOMPUTER
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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