M16C62_M Datasheet, PDF (539/615 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
4.1 Overview of External Buses
Memory and I/O external expansion can be connected to microcomputer easily by using external buses.
When memory expansion mode or microprocessor mode is selected for processor mode, some of the
pins function as the address bus, the data bus, and as control signals and this makes the external buses
be able to operate.
When accessing an external area, 8-bit data bus width or 16-bit data bus width can be selected, based on
the BYTE pin level. 16-bit width is used to access an internal area, regardless of the level of the BYTE pin.
Fix the BYTE pin either to “H” or “L” level. 8-bit and 16-bit data bus widths cannot be used together in an
external area.
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