M306H7MG-XXXFP Datasheet, PDF (14/329 Pages) Renesas Technology Corp – SINGLE-CHIP 16-BIT CMOS MICROCOMPUTER with DATA ACQUISITION CONTROLLER

M306H7MG-XXXFP/MC-XXXFP/FGFP
3. RESET
RESET
VCC2
VCC2
Recommended
operating
voltage
0V
RESET
0V
Equal to or less
than 0.2 VCC2
Equal to or less
than 0.2 VCC2
Apply the clock of 20 cycles or more to
the td(P-R) + XIN or XCIN pin. (Note 1)
Notes 1: When the STARTB pin=L, apply the clock of 20 cycles or more to the XIN pin.
When the STARTB pin=H, apply the clock of 20 cycles or more to the XCIN pin.
Notes 2: If VCC1 ≤ VCC2, the VCC1 voltage must be lower than that of VCC2 when the power is being turned on or off.
Figure 3.1 Example Reset Circuit
3.2 Software Reset
When the PM03 bit in the PM0 register is set to “1” (microcomputer reset), the microcomputer has its pins,
CPU, and SFR initialized. Then the program is executed starting from the address indicated by the reset vector.
Select the main clock for the CPU clock source, and set the PM03 bit to “1” with main clock oscillation
satisfactorily stable.
At software reset, some SFR’s are not initialized. Refer to “SFR”. Also, since the PM01 to PM00 bits in the PM0
register are not initialized, the processor mode remains unchanged.
3.3 Watchdog Timer Reset
Where the PM12 bit in the PM1 register is “1” (reset when watchdog timer underflows), the microcomputer
initializes its pins, CPU and SFR if the watchdog timer underflows. Then the program is executed starting from the
address indicated by the reset vector.
At watchdog timer reset, some SFR’s are not initialized. Refer to “SFR”. Also, since the PM01 to PM00 bits in the
PM0 register are not initialized, the processor mode remains unchanged.
Rev.2.10 Oct 25, 2006 Page 14 of 326
REJ03B0152-0210