; -*-asm-*-
include(`common.m4')

define(ticks_, 00)

        BRA r :reset
        BRA r :irq

;;; begin irq
irq:    PHA s

        LDA a T1CL
        DEC zp ticks_

        PLA s
        RTI s
;;; end irq


reset:  SEI i
        LDX # ff
        TXS i

        LDA # %00000001  ;; Set pins 0-7 on Port B to Output
        STA a DDRB

        LDA # %00000001
        STA a PORTB

        JSR a :continuous

count:  LDA # 25
        STA zp ticks_

loop:   LDA zp ticks_
        BPL r :loop
        LDA # %00000001
        EOR a PORTB
        STA a PORTB
        BRA r :count


;;; begin continuous
continuous:     LDA # %01000000
                STA a ACR
                LDA # 0e
                STA a T1CL
                LDA # 27
                STA a T1CH
                LDA # %11000000
                STA a IER
                CLI i
                RTS s
;;; end continuous


;;; begin oneshot
oneshot:        LDA # %00000000
                STA a ACR
                LDA # 50
                STA a T1CL
                LDA # c3
                STA a T1CH
_oneshot:       BIT a IFR
                BVC r :_oneshot ; IFR[6]==0
                LDA a T1CL    ; clear IFR[6]
                RTS s
;;; end oneshot