p10f200 Blink LED

This has a delay loop to turn on the LED, dely the loop, turn it off and repeat. This gives our eyes a chance to see the LED change state.

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#include "p10f200.inc"
; CONFIG
   __CONFIG _WDT_OFF & _CP_OFF & _MCLRE_OFF
   ORG 0x0000
INIT
   MOVLW  ~(1 << T0CS)     ; enable GPIO2
   OPTION    
   MOVLW ~(1 << GP2)       ; set and GP2 as an output
   TRIS GPIO
LOOP
   BSF GPIO, GP2           ; set GP2
   CALL DELAY              ; call DELAY subroutine
   BCF GPIO, GP2           ; reset GP2
   CALL DELAY              ; call DELAY subroutine
   GOTO LOOP               ; loop forever
 
DELAY                      ; start DELAY subroutine here
    MOVLW D'162'               ; load initial value for the delay
    MOVWF 10                   ; copy the value to the register 0x10
    MOVWF 11                   ; copy the value to the register 0x11
DELAY_LOOP                 ; start delay loop
    DECFSZ 10, F               ; decrement the register 0x10 and check if not zero
    GOTO DELAY_LOOP            ; if not then go to the DELAY_LOOP label
    DECFSZ 11, F               ; else decrement the register 0x11, check if it is not 0
    GOTO DELAY_LOOP            ; if not then go to the DELAY_LOOP label
    RETLW 0                    ; else return from the subroutine
END

Charlieplexing LEDs