Freescale Semiconductor MC68HC08KH12 - Manual (Page 84)

Advance Information MC68HC(7)08KH12 — Rev. 1.1
84 Freescale Semiconductor
7.8.2 Reset Status Register (RSR)
This register contains six 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.
;
;
;
This code works if the H register has been pushed onto the stack in the break
service routine software. This code should be executed at the end of the
break service routine software.
HIBYTE EQU 5
LOBYTE EQU 6
; If not SBSW, do RTI
BRCLR SBSW,BSR, RETURN ;
;
See if wait mode or stop mode was exited
by break
TST LOBYTE,SP ; If RETURNLO is not zero,
BNE DOLO ; then just decrement low byte.
DEC HIBYTE,SP ; Else deal with high byte, too.
DOLO DEC LOBYTE,SP ; Point to WAIT/STOP opcode.
RETURN PULH
RTI
; Restore H register.
Address: $FE01
Bit 7 6 5 4 3 2 1 Bit 0
Read: POR PIN COP ILOP ILAD USB 0 0
Write:
POR: 1 0 0 0 0 0 0 0
= Unimplemented
Figure 7-21. Reset Status Register (RSR)