// Convert 16 bit binary to 5 BCD characters
// from an application note by Maxim Semiconductors
// http://pdfserv.maxim-ic.com/arpdf/software/DI_1298.asm

extern unsigned char NumH, NumL;
extern unsigned char TenK, Thou, Hund, Tens, Ones;

void bin2bcd(unsigned int r) {
  NumH = r >> 8;
  NumL = r & 0xff;
#asm
#include <aspic.h>

;**********************
; 16bit binary 2 BCD
;**********************
bin2bcd                         ; Takes number in NumH:NumL 
                                ; Returns decimal in 
                                ; TenK:Thou:Hund:Tens:Ones 
        swapf   _NumH,w 
        andlw   0x0f              
        addlw   0xf0             
        movwf   _Thou 
        addwf   _Thou,f 
        addlw   0xe2 
        movwf   _Hund 
        addlw   0x32 
        movwf   _Ones 

        movf    _NumH,w 
        andlw   0x0f 
        addwf   _Hund,f 
        addwf   _Hund,f 
        addwf   _Ones,f 
        addlw   0xe9 
        movwf   _Tens 
        addwf   _Tens,f 
        addwf   _Tens,f 

        swapf   _NumL,w 
        andlw   0x0f 
        addwf   _Tens,f 
        addwf   _Ones,f 

        rlf     _Tens,f 
        rlf     _Ones,f 
        comf    _Ones,f 
        rlf     _Ones,f 

        movf    _NumL,w 
        andlw   0x0f 
        addwf   _Ones,f 
        rlf     _Thou,f 

        movlw   0x07 
        movwf   _TenK 

        movlw   0x0a                             
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 

#endasm
}