.include "labmac.i"
        .section .text
        .globl main

main:   MOVE.L #0xff, D1
        JSR outhxl
        MOVE.L #0x12345678, D1
        JSR outhxl
        MOVE.L #0xABCDEF00, D1
        JSR outhxl
        MOVE.L #0xA70C, D1
        JSR outhxl
        RTS



outhxl:	ROL.L	#8, D1       | put 1. byte (left) in position
      	JSR	outhex         | call output
       	ROL.L	#8, D1       | put 2. byte in position
      	JSR	outhex         | call output
       	ROL.L	#8, D1       | put 3. byte in position
      	JSR	outhex         | call output
       	ROL.L	#8, D1       | put 4. byte (right) in position
      	JSR	outhex         | call output

        MOVE.L  #10, D1    | print a new line
        CALLEXEC LCD_PutChar
      	RTS


outhex: MOVE.L  D1, D7          | copy input number
        LSR.B   #4, D1          | isolate left hex digit
        JSR     digit           | call output routine for 1st digit
        MOVE.L  D7, D1          | restore input
        AND.L   #0x0F, D1       | isolate right hex digit
        JSR     digit           | call output routine for 2nd digit
        MOVE.L  #' ', D1        | print a space character
        CALLEXEC LCD_PutChar
        MOVE.L  D7, D1          | restore input
        RTS

        Zero    = 48            | ascii code for 0
        LetterA = 55            | ascii code for A - 10

digit:  CMP.B   #10, D1         | Is digit within 0..9 ?
        BGE     abcdef
        ADD.B   #Zero, D1       | Yes: transform 0 ? 0, 1 ? 1
        CALLEXEC LCD_PutChar    | print as character
        RTS

abcdef: ADD.B   #LetterA, D1    | No:  transform 10 ? A, 11 ? B
        CALLEXEC LCD_PutChar    | print as character
        RTS