M16C Datasheet, PDF (29/262 Pages) Mitsubishi Electric Semiconductor – SINGLE-CHIP 16-BIT CMOS MICROCOMPUTER

Preliminary Specifications REV.B
Mitsubishi microcomputers
Specifications in this manual are tentative and subject to change.
M16C / 6N Group
SINGLE-CHIP 16-BIT CMOS MICROCOMPUTER
Bus Control
(6) Hold signal
The hold signal is used to transfer the bus privileges from the CPU to the external circuits. Inputting “L” to
the HOLD pin places the microcomputer in the hold state at the end of the current bus access. This status
is maintained and “L” is output from the HLDA pin as long as “L” is input to the HOLD pin. Table 3-7 shows
the microcomputer status in the hold state.
Table 3-7. Microcomputer status in hold state
Item
Oscillation
R/W signal, address bus, data bus, CS, BHE
Programmable I/O ports
P0, P1, P2, P3, P4, P5
P6, P7, P8, P9, P10
HLDA
Internal peripheral circuits
ALE signal
Status
ON
Floating
Floating
Maintains status when hold signal is received
Output “L”
ON (but watchdog timer stops)
Undefined
(7) BCLK output
The output of the internal clock φ can be selected using bit 7 of the processor mode register 0 (address
000416) (Note). The output is floating when bit 7 is set to “1”.
Note: Before attempting to change the contents of the processor mode register 0, set bit 1 of the protect
register (address 000A16) to “1”.
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