Code Optimisation (Digital FAHRENEHIT Thermometer)

;
;  Jake's modified 13+ bit 0000..9999 bin-to-dec algorithm
;
;   input: binh:binl -> 0x0000..0x270F (0..9999)
;  output: thou -> 0..9
;          huns -> 0..9
;          tens -> 0..9
;          ones -> 0..9
;
;  19 words, 4 or 5 variables, 14..8330 cycles  (Mike, K8LH)
;
        radix   dec

        clrf    thou            ;
        movlw   -10             ; wreg = -10
resHuns movwf   huns            ; set huns = -10
resTens movwf   tens            ; set tens = -10
div10z  addwf   binl,F          ; binl = binl - 10, borrow?
        skpc                    ; no, skip, else
        decf    binh,F          ; decrement hi byte
        btfsc   binh,7          ; negative? no, skip, else
        goto    b2dwrap         ; wrap up (borrow/underflow)
        incfsz  tens,F          ; tens overflow? yes, skip, else
        goto    div10z          ; loop
        incfsz  huns,F          ; huns overflow? yes, skip, else
        goto    resTens         ; reset 'tens' & loop
        incf    thou,F          ; bump 'thou'
        goto    resHuns         ; reset 'huns' & 'tens' & loop
b2dwrap subwf   huns,F          ; fix huns
        subwf   tens,F          ; fix tens
        subwf   binl,W          ; fix ones
        movwf   ones            ;