M16C62_M Datasheet, PDF (541/615 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
4.2.2 Chip Selects and Address Bus
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Chip selects (P44/CS0 through P47/CS3) are output in areas resulting from dividing a 1-M byte
memory space into four. To use the chip select, the chip select output must be enabled by setting the
chip select control register. Figure 4.2.2 shows addresses in which chip selects become active (“L”).
Since the extent of the internal area and the external area in memory expansion mode is different from
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those in microprocessor mode, there is a difference between areas for which CS0 is output. When an
internal ROM/RAM area is being accessed, no chip select is output, and the address bus does not
change (the address of the external area that was accessed previously is held).
0000016
003FF16
0040016
XXXXX16
SFR area
Internal RAM area
Internal reserved area
03FFF16
0400016
07FFF16
0800016
27FFF16
2800016
2FFFF16
3000016
CFFFF16
D000016
Internal reserved area
YYYYY16
FFFFF16
Internal ROM area
RAM size
3K bytes
4K bytes
5K bytes
10K bytes
20K bytes
Address XXXXX16
00FFF16
013FF16
017FF16
02BFF16
053FF16
ROM size Address YYYYY16
32K bytes
F800016
64K bytes
F000016
96K bytes
E800016
128K bytes
256K bytes
E000016
C000016
CS3
0400016 to 07FFF16 (16K)
CS2
0800016 to 27FFF16 (128K)
CS1
2800016 to 2FFFF16 (32K)
CS0
3000016 to CFFFF16 (640K)
3000016 to F7FFF16 (800K)
CS3
0400016 to 07FFF16 (16K)
CS2
0800016 to 27FFF16 (128K)
CS1
2800016 to 2FFFF16 (32K)
CS0
3000016 to FFFFF16 (832K)
Memory expansion mode
Microprocessor mode
Note : These memory maps show an instance in which PM13 is set to 0; but in the case of products in which the internal
RAM and the internal ROM are expanded to over 15 Kbytes and 192 Kbytes, respectively, they show an instance
in which PM13 is set to 1.
Figure 4.2.2. Addresses in which chip selects turn active (“L”)
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