mirror of
https://github.com/cc65/cc65.git
synced 2024-12-24 11:31:31 +00:00
53 lines
961 B
ArmAsm
53 lines
961 B
ArmAsm
;
|
|
; IRQ handling (Gamate version)
|
|
;
|
|
|
|
.export initirq, doneirq, IRQStub
|
|
|
|
.import __INTERRUPTOR_COUNT__, callirq_y
|
|
|
|
.include "gamate.inc"
|
|
.include "extzp.inc"
|
|
|
|
; ------------------------------------------------------------------------
|
|
.segment "INIT"
|
|
|
|
; 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
|