A quick search didn't show anything up, at least nothing with code.  I was =
just wondering if anyone else may have done this differently/better.  Here =
is how I did it.
It's a 5 minute (approx.) loop with 4 timer variables.  If I had to figure =
exact timing, I believe it would cause injury to my brain; so we'll go ahea=
d and say that timing isn't critical.  LED_MASK is just a xor value to togg=
le the GP pin attached to the speaker.  There also happens to be an LED con=
nected to the same pin.  It adds about a half second to the loop.
CODE BEGINS HERE
#include p10f200.inc
    ; set up the chip and do other stuff
Delay5m
    ; do the things    ; 6 instruction overhead in here which is irrelevant=
 to the beeping
    decfsz  TimerL,f    goto    Delay5m
    btfss   Beep,DoIBeep    goto    $ + 3    movlw   LED_MASK              =
  ; Sound a tone to remind the user that    xorwf   GPIO,f                 =
 ; the door is open.
    decfsz  TimerH,f    goto    Delay5m
    movf    TimerE,W                ; Sound tone during 6/256 TimerE iterat=
ions    andlw   b'11111000'             ; Throw out the lower 3 bits.    xo=
rlw   b'11111000'             ; Compare the upper 5.    btfss   STATUS,Z   =
 goto    $ + 3    movlw   1    xorwf   Beep,f

    decfsz  TimerE,f    goto    Delay5m
    decfsz  TimerW,f    goto    Delay5m
; end of the loop 		 	   		 =20
--=20
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