4cade/src/hw.vbl.init.a
2021-01-04 10:51:06 -08:00

52 lines
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;license:MIT
;(c) 2020 by qkumba
;
; Identify platform and construct appropriate VBL routine
romid = $FBB3
; $38=][, $EA=][+, $06=//e compatible
ROMID_IIECOMPAT = 6
romid_ec = $FBC0
; $EA=//e original, $E0=//e enhanced, $E1=//e EDM, $00=//c
romid_mac = $FBDD
ROMID_IIECARD = 2
; IIGS
idroutine = $FE1F ; SEC, JSR $FE1F, BCS notgs
BuildVBLFunction
ldx romid
cpx #ROMID_IIECOMPAT
bne @build_none ; not a //e
lda romid_ec
beq @build_iic ; //c family
lda romid_mac
cmp #ROMID_IIECARD
beq @build_none ; broken in some versions, disable
sec
jsr idroutine ; check for IIgs
bcs @NotGS
lda #$30
sta patch_VBL_iigs1
lda #$10
sta patch_VBL_iigs2
@NotGS
rts
@build_iic
sta patch_VBL_iic2+1
lda #$70
sta patch_VBL_iic1+1
lda #$10
sta patch_VBL_iic3
lda #<iWaitForVBL
sta WaitForVBL+1
lda #>iWaitForVBL
sta WaitForVBL+2
lda #$4C
sta UnwaitForVBL
rts
@build_none
lda #$60
sta WaitForVBL
rts