Multiplexer address control..

[Mike, K8LH]

t'would be simpler/faster still if you were to use the B3..B0 pins as both the 'control' variable and 'control' I/O;

RES_VECT  CODE    0x0000            ; processor reset vector
    GOTO    START                   ; go to beginning of program
; TODO ADD INTERRUPTS HERE IF USED
MAIN_PROG CODE                      ; let linker place main program
START
 

        movlw   0x30            ; B7..B4 other I/O, B3..B0 = control
        movwf   LATB            ;
lopo
        incf    LATB,W          ; B3..B0 bits = control, 0..15
        xorwf   LATB,W          ; wreg = differences
        andlw   0x0F            ; ignore B7..B4 bits (and control mod 16 for free)
        xorwf   LATB,F          ; update B3..B0 bits, 0..15
 
        GOTO    lopo