M306H7MG-XXXFP Datasheet, PDF (35/329 Pages) Renesas Technology Corp – SINGLE-CHIP 16-BIT CMOS MICROCOMPUTER with DATA ACQUISITION CONTROLLER

M306H7MG-XXXFP/MC-XXXFP/FGFP
4. CLOCK GENERATION CIRCUIT
4.4.2 Wait Mode
In wait mode, the CPU clock is turned off, so are the CPU (because operated by the CPU clock) and the
watchdog timer. Because the main clock and sub clock are on, the peripheral functions using these clocks keep
operating.
• Peripheral Function Clock Stop Function
If the CM02 bit is “1” (peripheral function clocks turned off during wait mode), the f1, f2, f8, f32, f1SIO, f8SIO,
f32SIO and fAD clocks are turned off when in wait mode, with the power consumption reduced that much.
However, fC32 remains on.
• Entering Wait Mode
The microcomputer is placed into wait mode by executing the WAIT instruction.
• Pin Status During Wait Mode
Pin Status During Wait Mode is shown in Table 4.2.
• Exiting Wait Mode
The microcomputer is moved out of wait mode by a hardware reset, NMI interrupt or peripheral function
interrupt.
If the microcomputer is to be moved out of exit wait mode by a hardware reset or NMI interrupt, set the
peripheral function interrupt priority ILVL2 to ILVL0 bits to “0002” (interrupts disabled) before executing the
WAIT instruction.
The peripheral function interrupts are affected by the CM02 bit. If CM02 bit is “0” (peripheral function clocks
not turned off during wait mode), all peripheral function interrupts can be used to exit wait mode. If CM02 bit
is “1” (peripheral function clocks turned off during wait mode), the peripheral functions using the peripheral
function clocks stop operating, so that only the peripheral functions clocked by external signals can be used to
exit wait mode.
Rev.2.10 Oct 25, 2006 Page 35 of 326
REJ03B0152-0210