6502/cc65
1
0
Fork 0
mirror of https://github.com/cc65/cc65.git synced 2026-04-23 23:17:45 +00:00
Code Issues Projects Releases Wiki Activity

Apple2: Dynamic IIe check on a2_lo_tgi

Browse Source
This commit is contained in:
Colin Leroy-Mira
2025-05-28 08:40:51 +02:00
committed by Oliver Schmidt
parent a9ab23ad51
commit 0122307399
5 changed files with 36 additions and 32 deletions
Download Patch File Download Diff File Expand all files Collapse all files
libsrc/apple2/waitvsync.s
+9 -14
View File
@@ -13,31 +13,28 @@
.include "apple2.inc"
_waitvsync:
.ifndef __APPLE2ENH__
bit machinetype ; IIe/enh?
bpl out ; No, silently fail
.endif
bit ostype
bmi iigs ; $8x
bvs iic ; $4x
.ifndef __APPLE2ENH__
bit machinetype ; IIe/enh?
bmi :+
lda #$FF ; ][+ Unsupported
tax
rts
.endif
; Apple IIe
: bit RDVBLBAR
bpl :- ; Blanking
: bit RDVBLBAR
bmi :- ; Drawing
bpl out
rts
; Apple IIgs TechNote #40, VBL Signal
iigs: bit RDVBLBAR
bmi iigs ; Blanking
: bit RDVBLBAR
bpl :- ; Drawing
bmi out
rts
; Apple IIc TechNote #9, Detecting VBL
iic: php
@@ -53,6 +50,4 @@ iic: php
bit DISVBL
: sta IOUDISON ; IIc Tech Ref Man: The firmware normally leaves IOUDIS on.
plp
out: lda #$00
tax
rts
out: rts