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cc65/libsrc/vic20/irq.s
Oliver Schmidt 419eb700b5 Renamed INITBSS to INIT and INIT to ONCE.
The way we want to use the INITBSS segment - and especially the fact that it won't have the type bss on all ROM based targets - means that the name INITBSS is misleading. After all INIT is the best name from my perspective as it serves several purposes and therefore needs a rather generic name.

Unfortunately this means that the current INIT segment needs to be renamed too. Looking for a short (ideally 4 letter) name I came up with ONCE as it contains all code (and data) accessed only once during initialization.
2016-03-06 21:27:19 +01:00

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ArmAsm

;
; IRQ handling (Vic20 version)
;
.export initirq, doneirq
.import callirq
.include "vic20.inc"
; ------------------------------------------------------------------------
.segment "ONCE"
initirq:
lda IRQVec
ldx IRQVec+1
sta IRQInd+1
stx IRQInd+2
lda #<IRQStub
ldx #>IRQStub
jmp setvec
; ------------------------------------------------------------------------
.code
doneirq:
lda IRQInd+1
ldx IRQInd+2
setvec: sei
sta IRQVec
stx IRQVec+1
cli
rts
; ------------------------------------------------------------------------
.segment "LOWCODE"
IRQStub:
cld ; Just to be sure
jsr callirq ; Call the functions
jmp IRQInd ; Jump to the saved IRQ vector
; ------------------------------------------------------------------------
.data
IRQInd: jmp $0000