;***** STK600 LEDS and SWITCH demonstration
.include "m2560def.inc"
.def Temp =r16 ; Temporary register
.def Delay =r17 ; Delay variable 1
.def Delay2 =r18 ; Delay variable 2
;***** Initialization
RESET:
    ser Temp
    out DDRB,Temp       ; Set PORTB to output
;**** Test input/output
LOOP:
    out PORTB,temp      ; Update LEDS
    sbis    PIND,0x00       ; If (Port D, pin0 == 0)
    inc Temp            ; then count LEDS one down
    sbis    PIND,0x01       ; If (Port D, pin1 == 0)
    dec Temp            ; then count LEDS one up
    sbis    PIND,0x02       ; If (Port D, pin2 == 0)
    ror Temp            ; then rotate LEDS one right
    sbis    PIND,0x03       ; If (Port D, pin3 == 0)
    rol Temp            ; then rotate LEDS one left
    sbis    PIND,0x04       ; If (Port D, pin4 == 0)
    com Temp            ; then invert all LEDS
    sbis    PIND,0x05       ; If (Port D, pin5 == 0)
    neg Temp            ; then invert all LEDS and add 1
    sbis    PIND,0x06       ; If (Port D, pin6 == 0)
    swap    Temp            ; then swap nibbles of LEDS
    ;**** Now wait a while to make LED changes visible.
    DLY:
    dec Delay
    brne    DLY
    dec Delay2
    brne    DLY
    rjmp    LOOP            ; Repeat loop forever