Converting 2-Digit Hex to Decimal ASCII Code for Display

For example, MCU processes hex number. If the user wishes to display the value code of a counter in a MCU, a conversion to decimal ASCII code will be required. Other wise, when the counter goes up to "11", the actual value in the MCU would be 0x0A, and the corresponding ASCII characters that will be displayed are "0 :"

The following code converts a hex value to decimal values, and put it in 3 different registers as decimal values. From there the user can display them as ASCII characters:

; *************************************************************
 ; HexToDec: Converts an Hexa in W in 3 decimals.
 ;   Args: W with Hexa
 ;   Returns:
 ;     Ones     
 ;     W                Tens from 0 to 25
 ;     Tens     
 ;     Hund     
 ; *************************************************************
 HexToDec:
        MOVWF        Ones
        CLRF Tmp2
 
 ; Get the Units
HexToDec1:
       MOVLW        .10
       SUBWF        Ones,W
       BTFSS        _carry
            GOTO       HexToDec2
       MOVWF        Ones
       INCF Tmp2,F
            GOTO HexToDec1

HexToDec2:
     MOVF Tmp2,W
      MOVWF        Tens
      CLRF Hund
HexToDec3:
       MOVLW        .10
       SUBWF        Tens,W
       BTFSS        _carry
            GOTO       HexToDec4
       MOVWF        Tens
       INCF Hund,F
            GOTO HexToDec3
 
HexToDec4:
       MOVF Tmp2,W
 
RETURN