.export _exit
.import getargs, argc, argv
.import __hinit, initconio, zerobss, pushax, doatexit
- .import _main,__filetab
+ .import _main,__filetab,getfd
.import __CODE_LOAD__, __BSS_LOAD__
+ .import __graphmode_used
.include "atari.inc"
sta appmsav
lda APPMHI+1
sta appmsav+1
+
+ jsr getmemtop ; adjust for graphics mode to use
- lda #<$8000
sta sp
sta APPMHI
- lda #>$8000
- sta sp+1 ; Set argument stack ptr
- sta APPMHI+1
+ stx sp+1 ; Set argument stack ptr
+ stx APPMHI+1
; set left margin to 0
lda #$FF
sta CH
-; ugly hack for now: set stdio stream handles
-; all to iocb #0
-; until we know where to go with fd<->iocb relation
-; this won't stay here!
+; set stdio stream handles
lda #0
- sta __filetab + 2
- sta __filetab + 4
+ jsr getfd
+ sta __filetab ; setup stdin
+ lda #0
+ jsr getfd
+ sta __filetab + 2 ; setup stdout
+ lda #0
+ jsr getfd
+ sta __filetab + 4 ; setup stderr
; Pass command line if present
rts
-.data
+; *** end of main startup code
+
+
+; calc. upper memory limit to use
+
+.proc getmemtop
+
+ ldy __graphmode_used
+ beq ignore ; mode 0 doesn't need adjustment
+ cpy #32
+ bcs ignore ; invalid value
+
+ tya
+ asl a
+ tay
+ lda MEMTOP
+ sec
+ sbc grmemusage,y
+ pha
+ lda MEMTOP+1
+ sbc grmemusage+1,y
+ tax
+ pla
+ rts
+
+ignore: lda MEMTOP
+ ldx MEMTOP+1
+ rts
+
+.endproc
+
+ .data
zpsave: .res zpspace
-
-.bss
+
+; memory usage of the different graphics modes (0-31)
+; values < 0 of "bytes needed" are mappped to 0
+; bytes needed ; mode ; val. of MEMTOP
+grmemusage:
+ .word 0 ; 0 ; 39967
+ .word 0 ;-318 ; 1 ; 40285
+ .word 0 ;-568 ; 2 ; 40535
+ .word 0 ;-558 ; 3 ; 40525
+ .word 0 ;-298 ; 4 ; 40265
+ .word 182 ; 5 ; 39785
+ .word 1182 ; 6 ; 38785
+ .word 3198 ; 7 ; 36769
+ .word 7120 ; 8 ; 32847
+ .word 7146 ; 9 ; 32821
+ .word 7146 ; 10 ; 32821
+ .word 7146 ; 11 ; 32821
+ .word 162 ; 12 ; 39805
+ .word 0 ;-328 ; 13 ; 40295
+ .word 3278 ; 14 ; 36689
+ .word 7120 ; 15 ; 32847
+ .word 0 ; 16 ; 39967
+ .word 0 ;-320 ; 17 ; 40287
+ .word 0 ;-572 ; 18 ; 40539
+ .word 0 ;-560 ; 19 ; 40527
+ .word 0 ;-296 ; 20 ; 40263
+ .word 184 ; 21 ; 39783
+ .word 1192 ; 22 ; 38775
+ .word 3208 ; 23 ; 36759
+ .word 7146 ; 24 ; 32821
+ .word 7146 ; 25 ; 32821
+ .word 7146 ; 26 ; 32821
+ .word 7146 ; 27 ; 32821
+ .word 160 ; 28 ; 39807
+ .word 0 ;-332 ; 29 ; 40299
+ .word 3304 ; 30 ; 36663
+ .word 7146 ; 31 ; 32821
+
+; the program used to get these values (Atari BASIC):
+; 100 FILE=0
+; 110 IF FILE=1 THEN OPEN #1,8,0,"D:FREEMEM.OUT"
+; 120 IF FILE<>1 THEN OPEN #1,8,0,"E:"
+; 200 DIM G(32)
+; 210 FOR I=0 TO 32:GRAPHICS I:GOSUB 1000:G(I)=VAL:NEXT I
+; 220 GRAPHICS 0
+; 230 FOR I=0 TO 31:PRINT #1;I;":",G(I);" - ";G(0)-G(I):NEXT I
+; 240 CLOSE #1
+; 999 END
+; 1000 VAL=PEEK(741)+256*PEEK(742)
+; 1010 RETURN
+
+ .bss
spsave: .res 1
appmsav: .res 1