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