mirror of
https://github.com/irmen/prog8.git
synced 2024-10-07 00:55:33 +00:00
42 lines
694 B
Lua
42 lines
694 B
Lua
%import textio
|
|
%zeropage dontuse
|
|
%option no_sysinit
|
|
|
|
main {
|
|
|
|
; $1F9C0 - $1F9FF PSG registers
|
|
|
|
sub start() {
|
|
c64.set_rasterirq(&irq.irq, 100, true)
|
|
|
|
sys.wait(100)
|
|
|
|
c64.restore_irq()
|
|
|
|
; uword freq = 1181
|
|
; cx16.vpoke(1, $f9c0, lsb(freq))
|
|
; cx16.vpoke(1, $f9c1, msb(freq))
|
|
; cx16.vpoke(1, $f9c2, %11111111) ; volume
|
|
; cx16.vpoke(1, $f9c3, %11000000) ; triangle waveform
|
|
}
|
|
}
|
|
|
|
|
|
irq {
|
|
uword counter = 0
|
|
|
|
sub irq() {
|
|
c64.EXTCOL++
|
|
ubyte xx
|
|
repeat 20 {
|
|
xx++
|
|
}
|
|
c64.EXTCOL--
|
|
|
|
@($0400) = lsb(counter)
|
|
@($0401) = msb(counter)
|
|
|
|
counter++
|
|
}
|
|
}
|