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|
;
; IRQ handling (Gamate version)
;
.export initirq, doneirq, IRQStub
.import __INTERRUPTOR_COUNT__, callirq_y
.include "gamate.inc"
.include "extzp.inc"
; ------------------------------------------------------------------------
.segment "ONCE"
; a constructor
;
initirq:
rts
; ------------------------------------------------------------------------
.code
; a destructor
;
doneirq:
rts
; ------------------------------------------------------------------------
; 256*32 interrupts in about 1minute 60s = 136hz
; -> guess 16384 clock cycles = 135,28hz (might be audio signal 1/512?)
IRQStub:
; A and Y are saved by the BIOS
;pha
;tya
;pha
ldy #<(__INTERRUPTOR_COUNT__ * 2)
beq @L1
txa
pha
jsr callirq_y
pla
tax
@L1: ;pla
;tay
;pla
rts
|
