MC908QL4 FREESCALE [Freescale Semiconductor, Inc], MC908QL4 Datasheet - Page 131

• Manufacturer Part Number: MC908QL4
• Description: M68HC08 Microcontrollers
• Manufacturer: FREESCALE [Freescale Semiconductor, Inc]

13.8 SIM Registers
The SIM has two memory mapped registers.
13.8.1 SIM Reset Status Register
This register contains seven flags that show the source of the last reset. Clear the SIM reset status
register by reading it. A power-on reset sets the POR bit and clears all other bits in the register.
POR — Power-On Reset Bit
PIN — External Reset Bit
COP — Computer Operating Properly Reset Bit
ILOP — Illegal Opcode Reset Bit
ILAD — Illegal Address Reset Bit (illegal attempt to fetch an opcode from an unimplemented
address)
MODRST — Monitor Mode Entry Module Reset bit
LVI — Low Voltage Inhibit Reset bit
Freescale Semiconductor
1 = Last reset caused by POR circuit
0 = Read of SRSR
1 = Last reset caused by external reset pin (RST)
0 = POR or read of SRSR
1 = Last reset caused by COP counter
0 = POR or read of SRSR
1 = Last reset caused by an illegal opcode
0 = POR or read of SRSR
1 = Last reset caused by an opcode fetch from an illegal address
0 = POR or read of SRSR
1 = Last reset caused by monitor mode entry when vector locations $FFFE and $FFFF are $FF after
0 = POR or read of SRSR
1 = Last reset caused by LVI circuit
0 = POR or read of SRSR
POR while IRQB = V
Read:
Write:
POR:
POR
Bit 7
1
Figure 13-19. SIM Reset Status Register (SRSR)
= Unimplemented
PIN
DD
6
0
MC68HC908QL4 Data Sheet, Rev. 7
COP
5
0
ILOP
4
0
ILAD
3
0
MODRST
2
0
LVI
1
0
Bit 0
0
0
SIM Registers
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