mirror of
https://github.com/a2-4am/4cade.git
synced 2024-09-24 08:00:22 +00:00
37 lines
1.2 KiB
Plaintext
37 lines
1.2 KiB
Plaintext
|
;license:MIT
|
||
|
|
;(c) 2019 by qkumba
|
||
|
|
|
||
|
|
!cpu 6502
|
||
|
|
!to "build/PRELAUNCH/STANDARD",plain
|
||
|
|
*=$106
|
||
|
|
|
||
|
|
;------------------------------------------------------------------------------
|
||
|
|
; Prelaunch
|
||
|
|
; code to set up and launch third-party code (either a self-running demo or
|
||
|
|
; an actual game)
|
||
|
|
; THIS IS NOT A FUNCTION. DO NOT CALL THIS DIRECTLY.
|
||
|
|
; must be run from main memory
|
||
|
|
;
|
||
|
|
; in: for first entry point, none
|
||
|
|
; for second entry point, the game must already be loaded in memory
|
||
|
|
; and ldrlo2/ldrhi2 must be the game entry point
|
||
|
|
; out: exits via JMP (ldrlo2), which is expected to exit via JMP |Prelaunch|
|
||
|
|
; (not here, but wherever it was copied to in main memory) or by
|
||
|
|
; manually enabling LC RAM then JMP |Reenter|
|
||
|
|
;------------------------------------------------------------------------------
|
||
|
|
lda $59 ; set up game entry point in stack page
|
||
|
|
ldy $5A ; (last ProRWTS load address - 1)
|
||
|
|
sec
|
||
|
|
sbc #$01
|
||
|
|
bcs +
|
||
|
|
dey
|
||
|
|
+ sta $1FE
|
||
|
|
sty $1FF
|
||
|
|
|
||
|
|
!source "src/PRELAUNCH/common.a"
|
||
|
|
|
||
|
|
ldx #$FD ; Jump to game entry point via stack pop.
|
||
|
|
txs
|
||
|
|
rts
|
||
|
|
End_Prelaunch
|