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.export Start, _exit
.import initlib, donelib, callmain
.import push0, _main, zerobss, copydata
; Linker generated symbols
.import __RAM_START__, __RAM_SIZE__
.include "zeropage.inc"
.include "gamate.inc"
Start:
; setup the CPU and System-IRQ
; Initialize CPU
sei
cld
ldx #0
stx ZP_IRQ_CTRL ; disable calling cartridge IRQ/NMI handler
; Set up stack and memory mapping
;ldx #$FF ; Stack top ($01FF)
dex
txs
; Clear the BSS data
jsr zerobss
; Copy the .data segment to RAM
jsr copydata
; Set up the stack
lda #<(__RAM_START__+__RAM_SIZE__)
ldx #>(__RAM_START__+__RAM_SIZE__)
sta sp
stx sp + 1
; Call module constructors
jsr initlib
lda #1
sta ZP_IRQ_CTRL ; enable calling cartridge IRQ/NMI handler
cli ; allow IRQ only after constructors have run
; Pass an empty command line
jsr push0 ; argc
jsr push0 ; argv
ldy #4 ; Argument size
jsr _main ; call the users code
; Call module destructors. This is also the _exit entry.
_exit:
jsr donelib ; Run module destructors
; reset (start over)
jmp Start
.export initmainargs
initmainargs:
rts
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