TITLE STRING (SIMPLFIED .EXE FORMAT)
.MODEL SMALL
;---------------------------------------------
.STACK 32
;---------------------------------------------
.DATA
MSG1 DB 10,13, "ENTER NUMBER : ", '$'
MSG2 DB 10,13, " ASCII CHARACTER: ", '$'
MSG3 DB 10,13, "IT PASSED SINGLE:", '$'

DIGIT1 DB ?,0ah, 0dh, "$"
DIGIT2 DB ?,0ah, 0dh, "$"
BCD DB ?,0ah, 0dh,"$"
TEMP DB ?,0ah, 0dh,"$"
;---------------------------------------------
.CODE
MAIN PROC FAR

MOV AX,@data
MOV DS,AX

START:

LEA DX,MSG1 ;prints message1
MOV AH,09H
INT 21H

MOV AH,01H ;TAKES INPUT AS HEX
INT 21H
MOV DIGIT1,AL


  ;EXIT
  CMP DIGIT1,1BH
  JE ENDING


  ;NOS ONLY
  CMP DIGIT1,31H
  JB START

  CMP DIGIT1,39H
  JA START

  ;subtract 30hex from DIGIT 1
  SUB AL,30H
  MOV DIGIT1,AL


MOV AH,01H ;TAKE INPUT2 AS HEX
INT 21H

;CONDITION FOR SINGLE DIGIT INPUT-NOT WORKING YET

; CMP DIGIT1,31H
 ;JB SINGLE

; CMP DIGIT1,39H
 ;JA SINGLE


SUB AL,30H
MOV DIGIT2,AL


MOV AH,DIGIT1
MOV AL,DIGIT2

MOV CL,4
ROL AH,CL
CONTINUE:
ADD AL,AH
MOV BCD,AL

  LEA DX,MSG2
  MOV AH,09
  INT 21H
     ;display ASCII CHAR
  MOV AH, 09
  LEA DX, BCD
  INT 21H

  MOV TEMP,00
  CALL PRINT_DOLLAR

 ENDING:
  MOV AH, 4CH
  INT 21H
MAIN ENDP


PRINT_DOLLAR PROC NEAR
   ;PRINT $
   MOV AL, 24H
   MOV AH, 02H
   MOV DL, AL
   INT 21H


   INC TEMP
   MOV AL,BCD
   CMP TEMP,AL ;NEED HEX CONVERTER. IF EQUAL TO BCD/ASCII VALUE, EXIT LOOP
   JE EXTEND

   JMP PRINT_DOLLAR
RET
PRINT_DOLLAR ENDP

EXTEND PROC NEAR

  JMP START
RET

EXTEND ENDP

SINGLE PROC NEAR ; IF ONLY INPUT 1 IS INPUTTED

  LEA DX,MSG3
  MOV AH,09
  INT 21H

 MOV AL,00
 MOV DIGIT2,AL

 MOV AH,DIGIT1
 MOV AL,DIGIT2
 JMP CONTINUE
RET
SINGLE ENDP


END MAIN