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added interruptor support

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mrdudz
2015-09-19 15:55:43 +02:00
parent 859604407b
commit 296489ba6c
8 changed files with 80 additions and 41 deletions
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40
libsrc/pce/crt0.s
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@@ -13,7 +13,7 @@
.import initlib, donelib
.import push0, _main, zerobss
.import initheap
.import tmp1,tmp2,tmp3
.import IRQStub
; Linker generated
.import __RAM_START__, __RAM_SIZE__
@@ -30,6 +30,7 @@
.importzp sp
.importzp ptr1,ptr2
.importzp tmp1,tmp2,tmp3
; ------------------------------------------------------------------------
; Place the startup code in a special segment.
@@ -158,39 +159,8 @@ _exit:
; reset the PCEngine (start over)
jmp start
; ------------------------------------------------------------------------
; System V-Blank Interupt
; FIXME: hooks should be provided so the user can abuse the IRQ
; ------------------------------------------------------------------------
_irq1:
pha
phx
phy
; increment the system tick counter
inc tickcount
bne @s1
inc tickcount + 1
bne @s1
inc tickcount + 2
bne @s1
inc tickcount + 3
@s1:
; Acknowlege interrupt
lda a:VDC_CTRL
ply
plx
pla
rti
_irq2:
rti
_nmi:
rti
_timer:
stz IRQ_STATUS
rti
.export initmainargs
initmainargs:
@@ -201,8 +171,8 @@ initmainargs:
; ------------------------------------------------------------------------
.segment "VECTORS"
.word _irq2 ; $fff6 IRQ2 (External IRQ, BRK)
.word _irq1 ; $fff8 IRQ1 (VDC)
.word _timer ; $fffa Timer
.word IRQStub ; $fff6 IRQ2 (External IRQ, BRK)
.word IRQStub ; $fff8 IRQ1 (VDC)
.word IRQStub ; $fffa Timer
.word _nmi ; $fffc NMI
.word start ; $fffe reset