TITLE SCORE
EXTRN POINTS:WORD, POINTS2:WORD
PUBLIC KEEP_SCORE, KEEP_SCORE_2

.MODEL SMALL
.CODE

KEEP_SCORE PROC
;  Input: Points are the number of points player 1 has.
;         Points2 are the number of points player 2 has.
;  Output score.  Player1 and Player2 are updated.
;
      PUSH AX           ;save registers.
      PUSH BX
      PUSH DX

      MOV   DX,0204H         ;set position for score
      CALL  SETPOS
      MOV   AL,'S'           ;set message SCORE:
      CALL  WCHAR            
      MOV   AL,'C'
      CALL  WCHAR
      MOV   AL,'O'
      CALL  WCHAR
      MOV   AL,'R'
      CALL  WCHAR
      MOV   AL,'E'
      CALL  WCHAR
      MOV   AL,':'
      CALL  WCHAR
      MOV   AL,' '
      CALL  WCHAR
      MOV   AX,POINTS         ; output score
      CALL  UTXTI
      
      POP DX                    ;restore registers.
      POP BX
      POP AX

RET
ENDP KEEP_SCORE

KEEP_SCORE_2 PROC

;  Output score is identical to Keep_Score, but is used for player 2.
;  Location of score is on right side.

      PUSH AX           ;save registers.
      PUSH BX
      PUSH DX

      MOV   DX,0218H         ; set position for score
      CALL  SETPOS
      MOV   AL,'S'           ; set message SCORE:
      CALL  WCHAR            ;write the character.
      MOV   AL,'C'
      CALL  WCHAR
      MOV   AL,'O'
      CALL  WCHAR
      MOV   AL,'R'
      CALL  WCHAR
      MOV   AL,'E'
      CALL  WCHAR
      MOV   AL,':'
      CALL  WCHAR
      MOV   AL,' '
      CALL  WCHAR
      MOV   AX,POINTS2         ; output score
      CALL  UTXTI
      POP DX
      POP BX
      POP AX
RET
ENDP KEEP_SCORE_2

WCHAR      PROC
      PUSH  AX             ; save registers
      PUSH  BX
      PUSH  BP
      SUB   BH,BH          ; set page zero
      MOV   AH,14          ; set code for write teletype
      INT   10H            ; write character
      POP   BP             ; restore registers
      POP   BX
      POP   AX
      RET                  ; return to caller
WCHAR      ENDP

UTXTI    PROC
      PUSH  CX             ; save registers
      PUSH  DX
      MOV   CX,10          ; divide input argument by 10
      SUB   DX,DX
      DIV   CX
;
;  We have the number / 10 in AX, and number mod 10 in DX. If the
;  value in AX is non-zero, we make a recursive call to output it
;
      OR    AX,AX          ; test non-zero quotient
      JZ    UTX2           ; jump if zero
      CALL  UTXTI          ; else output upper digits
;
;  Here we output the remainder from the division as the last digit
;
UTX2: MOV   AL,DL          ; remainder to AL
      OR    AL,'0'         ; convert to ASCII
      CALL  WCHAR          ; write last digit
      POP   DX             ; restore registers
      POP   CX
      RET                  ; return to caller
UTXTI      ENDP

SETPOS      PROC
      PUSH  AX            ; save registers
      PUSH  BX
      MOV   BH,0          ; set cursor
      MOV   AH,2
      INT   10H
      POP   BX            ; restore registers
      POP   AX
      RET                 ; return to caller
SETPOS      ENDP

END