* memory segments
STACK   equ     $00ff
EEPROM  equ     $f800

* motor port location
MOTORS  equ     $1004
        
* interrupt vector
IRQ     equ     $fff2

* constants for configuration register
OPTION  equ     $1039
IRQE    equ     %00100000

* code area
        org     EEPROM

start
* need to set up the option register ASAP
        ldaa    #IRQE
        staa    OPTION

* set up stack pointer
        lds     #STACK

* Enable interrupts.  Note IRQ has no local mask
        cli

* main loop
mloop
        wai     * standby
        bra     mloop

* IRQ interrupt handler.  We'll just invert the state of the LEDs so
* we can watch them flash 
irqhan  
        com     MOTORS
        rti

* interrupt vector
        org     IRQ
        fdb     irqhan

        end             start