i learned a few this about the sleep. here is a code segment from my 58
project, i haven't ordered the 508's yet.
note that you must reload the OSCCAL every time and also the OPTION
register, but most of all, and i don't understand why you must reload the
TRIS register. even though outputs remain active during sleep, when the
processor resets it changes them to the input mode.


Reset
        movwf   OSCCAL
Start
      movlw   B'11001111'
      OPTION
      movlw   H'FF'           ; set all ports high
      movwf   PORTB
      movlw   B'10110001'     ; Port B
      TRIS    PORTB
      btfss   STATUS,4        ; wakeup from sleep?
      goto    wakeup
power_on_reset  clrf    bit_variables


michael