;
; Startup code for cc65 (C128 version)
;

	.export		_exit
	.export		__STARTUP__ : absolute = 1      ; Mark as startup
	.import		initlib, donelib
	.import		zerobss
	.import		push0, callmain
	.import		RESTOR, BSOUT, CLRCH
	.import		__RAM_START__, __RAM_SIZE__, __STACKSIZE__
	.importzp	ST

	.include	"zeropage.inc"
	.include	"c128.inc"


; ------------------------------------------------------------------------
; Startup code

.segment	"STARTUP"

Start:

; Switch to the second charset

	lda	#14
	jsr	BSOUT

; Before doing anything else, we have to setup our banking configuration.
; Otherwise just the lowest 16K are actually RAM. Writing through the ROM
; to the underlying RAM works, but it is bad style.

	lda	MMU_CR		; Get current memory configuration...
	pha			; ...and save it for later
	lda	#MMU_CFG_CC65	; Bank0 with kernal ROM
	sta	MMU_CR

; Save the zero page locations we need

	ldx	#zpspace-1
L1:	lda	sp,x
	sta	zpsave,x
	dex
	bpl	L1

; Clear the BSS data

	jsr	zerobss

; Save system stuff and setup the stack

	pla		 	; Get MMU setting
	sta	mmusave

	tsx
	stx	spsave	 	; Save the system stack pointer

	lda	#<(__RAM_START__ + __RAM_SIZE__ + __STACKSIZE__)
	sta	sp
	lda	#>(__RAM_START__ + __RAM_SIZE__ + __STACKSIZE__)
	sta	sp+1		; Set argument stack ptr

; Call module constructors

	jsr	initlib

; Set the bank for the file name to our execution bank. We must do this,
; *after* calling constructors, because some of them may depend on the
; original value of this register.

	lda	#0
	sta	FNAM_BANK

; Push arguments and call main()

	jsr	callmain

; Back from main (this is also the _exit entry). Run module destructors

_exit:  pha			; Save the return code on stack
	jsr	donelib

; Copy back the zero page stuff

	ldx	#zpspace-1
L2:	lda	zpsave,x
	sta	sp,x
	dex
	bpl	L2

; Place the program return code into ST

	pla
	sta	ST

; Reset the stack and the memory configuration

	ldx	spsave
	txs
	ldx	mmusave
	stx	MMU_CR

; Done, return to BASIC

	rts

; ------------------------------------------------------------------------
; Data

.segment	"ZPSAVE"

zpsave:	.res	zpspace

; ------------------------------------------------------------------------

.bss

spsave:	.res	1
mmusave:.res	1