; Startup code for cc65 (ATARI version)
;
; Contributing authors:
-; Mark Keates
-; Freddy Offenga
-; Christian Groessler
+; Mark Keates
+; Freddy Offenga
+; Christian Groessler
+; Stefan Haubenthal
;
-; This must be the *first* file on the linker command line
-;
-
- .export _exit
- .constructor initsp, 26
- .import initlib, donelib, callmain
- .import zerobss, pushax
- .import _main, __filetab, getfd
- .import __LOWCODE_LOAD__, __ZPSAVE_LOAD__
- .import __RESERVED_MEMORY__
-.ifdef DYNAMIC_DD
- .import __getdefdev
+ .export __STARTUP__ : absolute = 1 ; Mark as startup
+ .export _exit, start, excexit, SP_save
+
+ .import initlib, donelib
+ .import callmain, zerobss
+ .import __RESERVED_MEMORY__
+ .import __MAIN_START__, __MAIN_SIZE__
+ .import __LOWCODE_RUN__, __LOWCODE_SIZE__
+.ifdef __ATARIXL__
+ .import __STACKSIZE__
+ .import sram_init
+ .import scrdev
+ .import findfreeiocb
+ .forceimport sramprep ; force inclusion of the "shadow RAM preparation" load chunk
+ .include "save_area.inc"
.endif
.include "zeropage.inc"
- .include "atari.inc"
- .include "_file.inc"
+ .include "atari.inc"
; ------------------------------------------------------------------------
-; EXE header
- .segment "EXEHDR"
- .word $FFFF
- .word __LOWCODE_LOAD__
- .word __ZPSAVE_LOAD__ - 1
+.segment "STARTUP"
-; ------------------------------------------------------------------------
-; Actual code
+ rts ; fix for SpartaDOS / OS/A+
+ ; They first call the entry point from AUTOSTRT; and
+ ; then, the load address (this rts here).
+ ; We point AUTOSTRT directly after the rts.
- .segment "LOWCODE"
+; Real entry point:
- rts ; fix for SpartaDOS / OS/A+
- ; they first call the entry point from AUTOSTRT and
- ; then the load addess (this rts here).
- ; We point AUTOSTRT directly after the rts.
+start:
-; Real entry point:
+.ifdef __ATARIXL__
+ jsr sram_init
+.endif
-; Save the zero page locations we need
+; Clear the BSS data.
- ldx #zpspace-1
-L1: lda sp,x
- sta zpsave,x
- dex
- bpl L1
+ jsr zerobss
-; Clear the BSS data
+; Set up the stack.
- jsr zerobss
+ tsx
+ stx SP_save
-; setup the stack
+.ifdef __ATARIXL__
- tsx
- stx spsave
+ lda #<(__MAIN_START__ + __MAIN_SIZE__ + __STACKSIZE__)
+ ldx #>(__MAIN_START__ + __MAIN_SIZE__ + __STACKSIZE__)
+ sta sp
+ stx sp+1
-; report memory usage
+.else
- lda APPMHI
- sta appmsav ; remember old APPMHI value
- lda APPMHI+1
- sta appmsav+1
+; Report the memory usage.
- sec
- lda MEMTOP
- sbc #<__RESERVED_MEMORY__
- sta APPMHI ; initialize our APPMHI value
- lda MEMTOP+1
- sbc #>__RESERVED_MEMORY__
- sta APPMHI+1
+ lda APPMHI
+ ldx APPMHI+1
+ sta APPMHI_save ; remember old APPMHI value
+ stx APPMHI_save+1
-; Call module constructors
+ sec
+ lda MEMTOP
+ sbc #<__RESERVED_MEMORY__
+ sta APPMHI ; initialize our APPMHI value
+ sta sp ; set up runtime stack part 1
+ lda MEMTOP+1
+ sbc #>__RESERVED_MEMORY__
+ sta APPMHI+1
+ sta sp+1 ; set up runtime stack part 2
- jsr initlib
-.ifdef DYNAMIC_DD
- jsr __getdefdev
.endif
-; set left margin to 0
+; Call the module constructors.
- lda LMARGN
- sta old_lmargin
- lda #0
- sta LMARGN
+ jsr initlib
-; set keyb to upper/lowercase mode
+; Set the left margin to 0.
- ldx SHFLOK
- stx old_shflok
- sta SHFLOK
+ lda LMARGN
+ sta LMARGN_save
+ ldy #0
+ sty LMARGN
-; Initialize conio stuff
+; Set the keyboard to upper-/lower-case mode.
- lda #$FF
- sta CH
+ ldx SHFLOK
+ stx SHFLOK_save
+ sty SHFLOK
-; set stdio stream handles
+; Initialize the conio stuff.
- lda #0
- jsr getfd
- sta __filetab + (0 * .sizeof(_FILE)); setup stdin
- lda #0
- jsr getfd
- sta __filetab + (1 * .sizeof(_FILE)); setup stdout
- lda #0
- jsr getfd
- sta __filetab + (2 * .sizeof(_FILE)); setup stderr
+ dey ; Set Y to $FF
+ sty CH ; remove keypress which might be in the input buffer
-; Push arguments and call main
+; Push the command-line arguments; and, call main().
- jsr callmain
+ jsr callmain
-; Call module destructors. This is also the _exit entry.
+; Call the module destructors. This is also the exit() entry.
-_exit: jsr donelib ; Run module destructors
+_exit: ldx SP_save
+ txs ; Restore stack pointer
-; Restore system stuff
+; Restore the system stuff.
- ldx spsave
- txs ; Restore stack pointer
+excexit:jsr donelib ; Run module destructors; 'excexit' is called from the exec routine
-; restore left margin
+; Restore the left margin.
- lda old_lmargin
- sta LMARGN
+ lda LMARGN_save
+ sta LMARGN
-; restore kb mode
+; Restore the kb mode.
- lda old_shflok
- sta SHFLOK
+ lda SHFLOK_save
+ sta SHFLOK
-; restore APPMHI
+; Restore APPMHI.
- lda appmsav
- sta APPMHI
- lda appmsav+1
- sta APPMHI+1
+ lda APPMHI_save
+ ldx APPMHI_save+1
+ sta APPMHI
+ stx APPMHI+1
-; Copy back the zero page stuff
+.ifdef __ATARIXL__
- ldx #zpspace-1
-L2: lda zpsave,x
- sta sp,x
- dex
- bpl L2
+; Atari XL target stuff...
-; turn on cursor
+ lda PORTB_save
+ sta PORTB
+ lda RAMTOP_save
+ sta RAMTOP
+ lda MEMTOP_save
+ ldx MEMTOP_save+1
+ sta MEMTOP
+ stx MEMTOP+1
- inx
- stx CRSINH
-; Back to DOS
+; Issue a GRAPHICS 0 call (copied'n'pasted from the TGI drivers), in
+; order to restore screen memory to its default location just
+; before the ROM.
- rts
+ jsr findfreeiocb
-; *** end of main startup code
+ ; Reopen it in Graphics 0
+ lda #OPEN
+ sta ICCOM,x
+ lda #OPNIN | OPNOT
+ sta ICAX1,x
+ lda #0
+ sta ICAX2,x
+ lda #<scrdev
+ sta ICBAL,x
+ lda #>scrdev
+ sta ICBAH,x
+ lda #3
+ sta ICBLL,x
+ lda #0
+ sta ICBLH,x
+ jsr CIOV_org
+; No error checking here, shouldn't happen(TM); and, no way to
+; recover anyway.
+
+ lda #CLOSE
+ sta ICCOM,x
+ jsr CIOV_org
-; setup sp
+.endif
+
+; Turn on the cursor.
+
+ ldx #0
+ stx CRSINH
+
+; Back to DOS.
-.segment "INIT"
+ rts
-initsp:
- lda APPMHI
- sta sp
- lda APPMHI+1
- sta sp+1
- rts
+; *** end of main startup code
-.segment "ZPSAVE"
+; ------------------------------------------------------------------------
-zpsave: .res zpspace
+.bss
- .bss
+SP_save: .res 1
+SHFLOK_save: .res 1
+LMARGN_save: .res 1
+.ifndef __ATARIXL__
+APPMHI_save: .res 2
+.endif
-spsave: .res 1
-appmsav: .res 1
-old_shflok: .res 1
-old_lmargin: .res 1
+; ------------------------------------------------------------------------
- .segment "AUTOSTRT"
- .word $02E0
- .word $02E1
- .word __LOWCODE_LOAD__ + 1
+.segment "LOWCODE" ; have at least one (empty) segment of LOWCODE, so that the next line works even if the program doesn't make use of this segment
+.assert (__LOWCODE_RUN__ + __LOWCODE_SIZE__ <= $4000 || __LOWCODE_RUN__ > $7FFF || __LOWCODE_SIZE__ = 0), warning, "'lowcode area' reaches into $4000..$7FFF bank memory window"
+; check for LOWBSS_SIZE = 0 not needed since the only file which uses LOWBSS (irq.s) also uses LOWCODE
+; check for LOWCODE_RUN > $7FFF is mostly for cartridges, where this segment is loaded high (into cart ROM)
+; there is a small chance that if the user loads the program really high, LOWCODE is above $7FFF, but LOWBSS is below -- no warning emitted in this case
projects / cc65 / blobdiff