M16C62_M Datasheet, PDF (559/615 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
BCLK
HOLD
HLDA
ALE
CSn
ADi
DBi
RD/WR
Indeterminate
HiZ
HiZ
HiZ
HiZ
Bus released
(1) (2) (3) (4)
(5)(6) (7) (8)
(1) An “L” level is input to the HOLD pin.
(2) HOLD is detected.
(3) The CPU releases the bus.
(4) An “L” is output to the HLDA pin.
(5) An “H” is input to the HOLD pin.
(6) An “H” is output to the HLDA pin.
(7) The CPU not releases the bus.
(8) The CPU resumes using the bus.
Figure 4.5.1. Example of releasing the external bus
4.6 Precautions for External Bus
(1) The external ROM version can operate only in the microprocessor mode, so be sure to per-
form the following:
• Connect the CNVSS pin to Vcc.
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