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112 lines
2.4 KiB
ArmAsm
112 lines
2.4 KiB
ArmAsm
;
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; Startup code for cc65 (Oric version)
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;
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; By Debrune Jérôme <jede@oric.org> and Ullrich von Bassewitz <uz@cc65.org>
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;
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; This must be the *first* file on the linker command line
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;
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.export _exit
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.import initlib, donelib
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.import callmain, zerobss
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.import __RAM_START__, __RAM_SIZE__, __BSS_LOAD__
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.include "zeropage.inc"
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.include "atmos.inc"
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; ------------------------------------------------------------------------
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; Oric tape header
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.segment "TAPEHDR"
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.byte $16, $16, $16 ; Sync bytes
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.byte $24 ; End of header marker
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.byte $00 ; $2B0
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.byte $00 ; $2AF
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.byte $80 ; $2AE Machine code flag
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.byte $C7 ; $2AD Autoload flag
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.dbyt __BSS_LOAD__ ; $2AB
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.dbyt __RAM_START__ ; $2A9
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.byte $00 ; $2A8
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.byte $00 ; Zero terminated name
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; ------------------------------------------------------------------------
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; Place the startup code in a special segment.
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.segment "STARTUP"
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; Save the zero page area we're about to use
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ldx #zpspace-1
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L1: lda sp,x
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sta zpsave,x ; Save the zero page locations we need
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dex
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bpl L1
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; Clear the BSS data
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jsr zerobss
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; Unprotect columns 0 and 1
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lda STATUS
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sta stsave
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and #%11011111
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sta STATUS
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; Save system stuff and setup the stack
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tsx
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stx spsave ; save system stk ptr
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lda #<(__RAM_START__ + __RAM_SIZE__)
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sta sp
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lda #>(__RAM_START__ + __RAM_SIZE__)
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sta sp+1 ; Set argument stack ptr
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; Call module constructors
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jsr initlib
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; Push arguments and call main()
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jsr callmain
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; Call module destructors. This is also the _exit entry.
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_exit: jsr donelib ; Run module destructors
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; Restore system stuff
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ldx spsave
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txs
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lda stsave
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sta STATUS
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; Copy back the zero page stuff
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ldx #zpspace-1
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L2: lda zpsave,x
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sta sp,x
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dex
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bpl L2
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; Back to BASIC
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rts
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; ------------------------------------------------------------------------
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; Data
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.data
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zpsave: .res zpspace
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.bss
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spsave: .res 1
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stsave: .res 1
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