M16C Datasheet, PDF (44/262 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
CWloacitkMGoedneerating Circuit
Wait Mode
When a WAIT instruction is executed, the BCLK stops and the microcomputer enters the wait mode. In this
mode, oscillation continues but the BCLK and watchdog timer may be stopped under certain conditions.
Refer to the section describing the watchdog timer. Writing “1” to the WAIT peripheral function clock stop bit
and executing a WAIT instruction stops the clock being supplied to the internal peripheral functions, allowing
power consumption to be reduced. Table 5-3 shows the status of the ports in wait mode.
Wait mode is cancelled by a hardware reset or interrupt. If an interrupt is used to cancel wait mode, the
microcomputer restarts using as BCLK the clock that had been selected when the WAIT instruction was
executed.
Table 5-3. Port status during wait mode
Pin
Memory expansion mode
Single-chip mode
Microprocessor mode
Address bus, data bus, CS0 to CS3 Retains status before wait mode
RD, WR, BHE, WRL, WRH
“H”
HLDA
“H”
BCLK
ALE
Port
CLKOUT
“H” (Note)
“H”
Retains status before wait mode Retains status before wait mode
When fC selected Valid only in single-chip mode Does not stop
When f8, f32 selected Valid only in single-chip mode Does not stop when the WAIT
peripheral function clock stop
bit is “0”.
When the WAIT peripheral
function clock stop bit is “1”,
the status immediately prior
to entering wait mode is main-
tained.
Note: BCLK is "H" only when the watchdog timer is stopped. Refer to the watchdog timer section for more
information
44