![](http://datasheet.mmic.net.cn/30000/M30956FKTGP_datasheet_2359453/M30956FKTGP_76.png)
5. Reset
5.2
Software Reset
When the PM03 bit in the PM0 register is set to 1 (The MCU is reset), the MCU resets the CPU, SFRs, and pins
assigned to ports and I/O pins for peripheral functions, and these pins are configured as input pins. Then the MCU
executes a program in an address indicated by the reset vector.
Set the PM03 bit to 1 while the main clock is selected as the source for the CPU clock and the main clock
oscillation is stable.
The software reset does not reset the following SFRs; PM01 to PM00 bits in the PM0 register, WDC5 bit in the
WDC register, and TCSPR register.
Processor mode remains unchanged since bits PM01 and PM00 in the PM0 register are not reset.
5.3
Watchdog Timer Reset
When the CM06 bit in the CM0 register is set to 1 (reset) and the watchdog timer underflows, the MCU resets the
CPU, SFRs, and pins assigned to ports and I/O pins for peripheral functions, and these pins are configured as input
pins. Then the MCU executes a program in an address indicated by the reset vector.
The watchdog timer reset does not reset the following SFRs; PM01 to PM00 bits in the PM0 register, WDC5 bit in
the WDC register, and TCSPR register.
Processor mode remains unchanged since bits PM01 and PM00 are not reset.
5.4
Internal Space
after reset.
Figure 5.3
CPU Register States after Reset
R0H
R0L
R1H
R1L
R2
R3
A0
A1
SB
FB
00h
0000h
000000h
Contents of addresses
FFFFFEh to FFFFFCh
00h
b15
b23
b0
0
X
b15
b0
b8 b7
XXXXh
XXXXXXh
b23
b15
b0
00h
XXXXh
XXXXXXh
b23
b15
b0
b7
User stack pointer (USP)
Interrupt stack pointer (ISP)
Interrupt table register (INTB)
Flag register (FLG)
General registers
High-speed interrupt registers
DMAC-associated registers
Save flag register (SVF)
Save PC register (SVP)
Vector register (VCT)
X
0
UIO B S Z D C
IPL
Data register (R0H/R0L)
Data register (R1H/R1L)
Data register (R2)
Data register (R3)
Address register (A0)
Address register (A1)
Static base register (SB)
Frame base register (FB)
DMA mode register (DMD0)
DMA mode register (DMD1)
DMA transfer count register (DCT0)
DMA transfer count register (DCT1)
DMA transfer count reload register (DRC0)
DMA transfer count reload register (DRC1)
DMA memory address register (DMA0)
DMA memory address register (DMA1)
DMA memory address reload register (DRA0)
DMA memory address reload register (DRA1)
DMA SFR address register (DSA0)
DMA SFR address register (DSA1)
Program counter (PC)
b15
b0
0: 0 after reset
X: undefined after reset