Lab1P1

;******************************************************************************
;*
;* CSE3215 Relocatable Assembly Source Code Template for the MC9S12DP256B
;* microcontroller.
;*
;* main.asm
;*
;* Jan 09, 2006
;*
;******************************************************************************

 NOLIST
 include    "mc9s12dp256.inc"   ; Register definitions.
 LIST

; export symbols
            XDEF Entry        ; export 'Entry' symbol
            ABSENTRY Entry    ; for absolute assembly: mark this as application entry point


MyRAMStart    EQU  $1000  ; absolute address to place my variablesMy
MyROMStart    EQU  $2000  ; absolute address to place my code/constant data

; variable/data section
            ORG MyRAMStart
; Insert here your data definition. For demonstration, temp_byte is used.
temp_byte   ds.b 1


; code section
            ORG MyROMStart
Entry:
            CLI                ; enable interrupts

            MOVB #1,temp_byte  ; just some demonstration code
            NOP                ; Insert here you own code

            MOVB #FF,DDRB      ; Set LED PORTB to be output
            CLC PTB            ; Clear contents of LED PORTB
            MOVB #00,DDRH      ; Set DDRH0-3 to be input
            LDAA #3E           ; Load 62 into accumulator A
            LDAB #C0           ; Load 192 into accumulator B

            BRA Entry  ; endless loop
Compare:
            CMPA PTH           ; Compare switch input register PORTH with the accumulator A(62)
            BHI Greater        ; Branch if A(62)>PTH
            CMPB PTH           ; Compare switch input register PORTH with accumulator B(192)
            BLO Less           ; Branch if PTH>192(B)
            MOVB #00,PORTB     ; Turn of both LEDs
            BRA Compare        ; Else repeat compare
Less:
            MOVB #01,PORTB     ; Turn on LED0(B0)
            BRA Compare
Greater:
            MOVB #80,PORTB     ; Turn on LED7(B7)
            BRA Compare        ; Branch back to beginning of compare