; A Level Computing Science Project: Car Burglar Alarm.
;
; This file declares all the constants for use with the
; Burglar Alarm Operating System, BugOS.
;
; (C) 1987, 2026 Rich Teer.


flags	*		&0000			; Various flags.
tries	*		&0001			; Number of attempts at entering code number.
sec100	*		&0002			; 1/100 second timer.
secs	*		&0003			; Number of seconds before timeout.
pclo	*		&0004			; PC lo.
pchi	*		&0005			; PC hi.
acc		*		&0006			; Accumulator store.
xreg	*		&0007			; X Register store.
yreg	*		&0008			; Y Register store.
sr		*		&0009			; Processor Status store.
temp	*		&000A			; Temporary storage.
enterd	*		&0200			; Entered password stored from here.

v1iorb	*		&8000			; VIA 1 I/O Register B.
v1iora	*		&8001			; VIA 1 I/O Register A.
v1ddrb	*		&8002			; VIA 1 Data Direction Register B.
v1ddra	*		&8003			; VIA 1 Data Direction Register A.
v1t1cl	*		&8004			; VIA 1 Timer1 Counter Low.
v1t1ch	*		&8005			; VIA 1 Timer1 Counter High.
v1t2cl	*		&8008			; VIA 1 Timer2 Counter Low.
v1t2ch	*		&8009			; VIA 1 Timer2 Counter High.
v1acr	*		&800B			; VIA 1 Auxiliary Control Register.
v1ifr	*		&800D			; VIA 1 Interrupt Flag Register.
v1ier	*		&800E			; VIA 1 Interrupt Enable Register.

doors	*		&02				; Mask to see if a door has been opened.
clock	*		&04				; Mask to see if timer is a delay or a clock.
timer2	*		&20				; Mask for Timer2 interrupt.

		LNK		bugos1			; Continue assembly with the actual BugOS code.
