LCD_STRING    EQU   $FF
LCD_INIT      EQU   $00
LCD_ASK_POS   EQU   $05
LCD_SET_POS   EQU   $06
EOT           EQU   $04


          ORG        $D000
LCD       PSHX
          PSHB
          CMPB       #LCD_STRING
          BEQ        PRSTRING       ;PRINT STRING
          CMPB       #LCD_INIT
          BEQ        DPINIT         ;DISPLAY INIT
          CMPB       #LCD_ASK_POS
          BEQ        HAALPOS        ;HAAL POSITIE
          CMPB       #LCD_SET_POS
          BLO        ZETPOS         ;ZET POSITIE
          BRA        PRCHAR         ;DEFAULT PRINT CHAR
          RTS


PRSTRING  LDAA       0,X
          CMPA       #$04           ;EOT
          BEQ        ENDPR
          STAA       $3000
          INX
          BRA        PRSTRING
ENDPR     PULB
          BRA        EINDLCD


PRCHAR    STAB       $3000
          PULB
          BRA        EINDLCD


DPINIT    LDAA       #$0
          STAA       $3000
          PULB
          BRA        EINDLCD


HAALPOS   PULB                     ;dummy
          LDAA       #$05
          STAA       $3000
          CLRA
          LDAB       $2000
          LDX        #$14
          IDIV
          PSHX
          TSY
          STAB       0,Y
          PULA
          PULB
          INCA
          INCB
          BRA        EINDLCD


ZETPOS    DECA
          PSHA
          LDAA       #$14
          DECB
          MUL
          PULA
          ABA
          STAA       $2000
          LDAA       #$6
          STAA       $3000
          PULB
          BRA        EINDLCD


EINDLCD   PULX
          RTS