I need to convert 16 bit binary to 4 BCD digits.  I searched the archives
and thought I had found just the right thing, so I more-or-less just pasted
it into my 16C877 code.  However, MPASM gives error messages on the lines
with the ds and $ directives.   I can't find any references to the $ (except
where it returns the PCL) in the MPASM user's guide.

Could someone please explain what I need to know in order to modify this
code to produce the desired result?

Thanks very much,

        Foster


(CODE FROM ARCHIVES FOLLOWS:)
;**********************************************************
; Binary-to-BCD.  Written by John Payson.
;
; Enter with 16-bit binary number in NumH:NumL.
; Exits with BCD equivalent in TenK:Thou:Hund:Tens:Ones.



NumH:   ds      1
NumL:   ds      1
TenK:   ds      1
Thou:   ds      1
Hund:   ds      1
Tens:   ds      1
Ones:   ds      1

Convert:                        ; Takes number in NumH:NumL
                                ; Returns decimal in
                                ; TenK:Thou:Hund:Tens:Ones
        swapf   NumH,w


        andlw   0x0f
        andlw   0xf0

        movwf   Thou
        addwf   Thou,f

        addlw   $E2
        movwf   Hund
        addlw   $32


        movwf   Ones

        movf    NumH,w
        andlw   $0F


        addwf   Hund,f
        addwf   Hund,f
        addwf   Ones,f
        addlw   $E9
        movwf   Tens
        addwf   Tens,f
        addwf   Tens,f

        swapf   NumL,w
        andlw   $0F
        addwf   Tens,f
        addwf   Ones,f

        rlf     Tens,f
        rlf     Ones,f
        comf    Ones,f
        rlf     Ones,f

        movf    NumL,w
        andlw   $0F
        addwf   Ones,f
        rlf     Thou,f

        movlw   $07
        movwf   TenK

                        ; At this point, the original number is
                        ; equal to
                        ;TenK*10000+Thou*1000+Hund*100+Tens*10+Ones ;
                        ;if those entities are regarded as two's
                        ;compliment ; binary.  To be precise, all of
                        ;them are negative ; except TenK.  Now the
                        ;number needs to be normal- ; ized, but this
                        ;can all be done with simple byte ; arithmetic.

        movlw   $0A                             ; Ten
Lb1:
        addwf   Ones,f
        decf    Tens,f
        btfss   3,0
         goto   Lb1
Lb2:
        addwf   Tens,f
        decf    Hund,f
        btfss   3,0
         goto   Lb2
Lb3:
        addwf   Hund,f
        decf    Thou,f
        btfss   3,0
         goto   Lb3
Lb4:
        addwf   Thou,f
        decf    TenK,f
        btfss   3,0
         goto   Lb4

        retlw   0

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