; Stefan Haubenthal
;
- .export _exit
.export __STARTUP__ : absolute = 1 ; Mark as startup
+ .export _exit, start
.import initlib, donelib
.import callmain, zerobss
- .import __STARTUP_LOAD__, __ZPSAVE_LOAD__, __BSS_LOAD__
.import __RESERVED_MEMORY__
- .import __RAM_START__, __RAM_SIZE__
- .import zpsave
- .import sram_init
-
+ .import __RAM_START__, __RAM_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 "save_area.inc"
; ------------------------------------------------------------------------
-; EXE header
-
-.segment "EXEHDR"
-
- .word $FFFF
-
-.if .defined(__ATARIXL__)
-.segment "MAINHDR"
-.endif
-
- .word __STARTUP_LOAD__
-.if .defined(__ATARIXL__)
- .word __BSS_LOAD__ - 1
-.else
- .word __ZPSAVE_LOAD__ - 1
-.endif
-
-; ------------------------------------------------------------------------
-; Actual code
.segment "STARTUP"
; Real entry point:
-.if .not .defined(__ATARIXL__) ; already done in previous load chunk
-
-; Save the zero page locations we need
-
- ldx #zpspace-1
-L1: lda sp,x
- sta zpsave,x
- dex
- bpl L1
-
-.else
-
- jsr sram_init
+start:
+.ifdef __ATARIXL__
+ jsr sram_init
.endif
; Clear the BSS data
; Setup the stack
tsx
- stx spsave
+ stx SP_save
+
+.ifdef __ATARIXL__
-.if .not .defined(__ATARIXL__)
+ lda #<(__RAM_START__ + __RAM_SIZE__ + __STACKSIZE__)
+ sta sp
+ lda #>(__RAM_START__ + __RAM_SIZE__ + __STACKSIZE__)
+ sta sp+1
+
+.else
; Report memory usage
lda APPMHI
- sta appmsav ; remember old APPMHI value
+ sta APPMHI_save ; remember old APPMHI value
lda APPMHI+1
- sta appmsav+1
+ sta APPMHI_save+1
sec
lda MEMTOP
sta APPMHI+1
sta sp+1 ; setup runtime stack part 2
-.else
-
- lda #<(__RAM_START__ + __RAM_SIZE__ - 1)
- sta sp
- lda #>(__RAM_START__ + __RAM_SIZE__ - 1)
- sta sp+1
-
.endif
; Call module constructors
; Set left margin to 0
lda LMARGN
- sta old_lmargin
+ sta LMARGN_save
ldy #0
sty LMARGN
; Set keyb to upper/lowercase mode
ldx SHFLOK
- stx old_shflok
+ stx SHFLOK_save
sty SHFLOK
; Initialize conio stuff
- dey ; Set X to $FF
- sty CH
+ dey ; Set Y to $FF
+ sty CH ; remove keypress which might be in the input buffer
; Push arguments and call main
; Restore system stuff
- ldx spsave
+ ldx SP_save
txs ; Restore stack pointer
; Restore left margin
- lda old_lmargin
+ lda LMARGN_save
sta LMARGN
; Restore kb mode
- lda old_shflok
+ lda SHFLOK_save
sta SHFLOK
-.if .not .defined(__ATARIXL__)
-
; Restore APPMHI
- lda appmsav
+ lda APPMHI_save
sta APPMHI
- lda appmsav+1
+ lda APPMHI_save+1
sta APPMHI+1
-.else
+.ifdef __ATARIXL__
; Atari XL target stuff...
- lda PORTB_save
- sta PORTB
- lda MEMTOP_save
- sta MEMTOP
- lda MEMTOP_save+1
- sta MEMTOP+1
- lda APPMHI_save
- sta APPMHI
- lda APPMHI_save+1
- sta APPMHI+1
-.endif
-
-
-; Copy back the zero page stuff
+ lda PORTB_save
+ sta PORTB
+ lda RAMTOP_save
+ sta RAMTOP
+ lda MEMTOP_save
+ sta MEMTOP
+ lda MEMTOP_save+1
+ sta MEMTOP+1
+
+
+; Issue a GRAPHICS 0 call (copied'n'pasted from TGI drivers) in
+; order to restore screen memory to its defailt location just
+; before the ROM.
+
+ jsr findfreeiocb
+
+ ; 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
- ldx #zpspace-1
-L2: lda zpsave,x
- sta sp,x
- dex
- bpl L2
+.endif
; Turn on cursor
- inx
+ ldx #0
stx CRSINH
; Back to DOS
.bss
-spsave: .res 1
-appmsav: .res 1
-old_shflok: .res 1
-old_lmargin: .res 1
-
- .segment "AUTOSTRT"
- .word RUNAD ; defined in atari.h
- .word RUNAD+1
- .word __STARTUP_LOAD__ + 1
+SP_save: .res 1
+SHFLOK_save: .res 1
+LMARGN_save: .res 1
+.ifndef __ATARIXL__
+APPMHI_save: .res 2
+.endif
projects / cc65 / blobdiff