; This program multiplexes the number 1234
; on the four 7-segment displays.

; Note: a logic 0 lights a display segment.

start:
	SETB P3.3				; |
	SETB P3.4				; | enable display 3
	MOV P1, #11111001B		; put pattern for 1 on display
	MOV P1, #0FFH			; clear the display
	CLR P3.3				; enable display 2
	MOV P1, #10100100B		; put pattern for 2 on display
	MOV P1, #0FFH			; clear the display
	CLR P3.4				; |
	SETB P3.3				; | enable display 1
	MOV P1, #10110000B		; put pattern for 3 on display
	MOV P1, #0FFh			; clear the display
	CLR P3.3				; enable display 0
	MOV P1, #10011001B		; put pattern for 4 on display
	MOV P1, #0FFH			; clear display
	JMP start				; jump back to start