M32C8A Datasheet, PDF (106/372 Pages) Renesas Technology Corp – RENESAS MCU M16C FAMILY / M32C/80 Series

M32C/8A Group
9. Clock Generation Circuits
9.5.2.3 Pin States in Wait Mode
Table 9.6 lists pin states in wait mode.
Table 9.6 Pin States in Wait Mode
Pin
States
Address bus, data bus, CS0 to CS3, BHE
Maintain the state immediately before entering wait mode
RD, WR, WRL, WRH
“H”
HLDA, BCLK
“H”
ALE
“L”
Ports
Maintain the state immediately before entering wait mode
CLKOUT
When fC is selected
Continue to output the clock
When f8, f32 are selected ^{• When the CM02 bit in the CM0 register is 0 (peripheral clocks}
do not stop in wait mode): Continue to output the clock
• When the CM02 bit is 1 (peripheral clocks stop in wait mode):
The clock is stopped and holds the level immediately before
entering wait mode
9.5.2.4 Exiting Wait Mode
Wait mode is exited by the hardware reset 1, hardware reset 2, NMI interrupt, Vdet4 detection interrupt, or
peripheral function interrupts.
As for a peripheral function interrupt that is not used to exit wait mode, set bits ILVL2 to ILVL0 in the Interrupt
Control Register for the peripheral function interrupt to 000b (interrupt disabled) before executing the WAIT
instruction.
The CM02 bit setting in the CM0 register affects the use of the peripheral function interrupts to exit wait mode.
When the CM02 bit is set to 0 (peripheral clocks do not stop in wait mode), any peripheral function interrupts
can be used to exit wait mode. When the CM02 bit is set to 1 (peripheral clocks stop in wait mode), the
peripheral functions clocked by the peripheral function clocks stop, and therefore, the peripheral function
interrupts cannot be used to exit wait mode. However, the peripheral functions clocked by the external clock
and fC32 do not stop regardless of the CM02 bit setting. Also, f2n, which uses the XIN clock (fXIND) or on-
chip oscillator clock as its clock source does not stop. The interrupts generated by the peripheral functions
which operate using these clocks can be used to exit wait mode.
When the MCU exits wait mode by the peripheral function interrupts or NMI interrupt, the CPU clock does not
change before and after the WAIT instruction is executed.
Table 9.7 lists interrupts to be used to exit wait mode and usage conditions.
Rev.1.00 Jul 15, 2007 Page 89 of 352
REJ09B0385-0100