6502/cc65
1
0
Fork 0
mirror of https://github.com/cc65/cc65.git synced 2024-07-03 06:29:36 +00:00
Code Issues Projects Releases Wiki Activity

Allow to run programs as ProDOS SYS files (beside BIN files). To do so detect at runtime if BASIC.SYSTEM is present by checking the "signature" of the last system bitmap byte.

Browse Source 
git-svn-id: svn://svn.cc65.org/cc65/trunk@4146 b7a2c559-68d2-44c3-8de9-860c34a00d81
This commit is contained in:
ol.sc 2009-09-11 16:27:20 +00:00
parent d9cdca75b6
commit aeccd3a776
1 changed files with 59 additions and 17 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

76
libsrc/apple2/crt0.s
View File

@ -99,14 +99,14 @@ _exit: ldx #<exit
jsr donelib jsr donelib
; Check for valid interrupt vector table entry number ; Check for valid interrupt vector table entry number
lda intnum lda int_num
beq exit beq exit
; Deallocate interrupt vector table entry ; Deallocate interrupt vector table entry
dec params ; Adjust parameter count dec i_param ; Adjust parameter count
jsr $BF00 ; MLI call entry point jsr $BF00 ; MLI call entry point
.byte $41 ; Dealloc interrupt .byte $41 ; Dealloc interrupt
.addr params .addr i_param
; Restore the original RESET vector ; Restore the original RESET vector
exit: ldx #$02 exit: ldx #$02
@ -128,8 +128,8 @@ exit: ldx #$02
ldx #$FF ldx #$FF
txs ; Re-init stack pointer txs ; Re-init stack pointer
; Back to DOS ; We're done
jmp DOSWARM jmp (done)
; ------------------------------------------------------------------------ ; ------------------------------------------------------------------------
@ -159,25 +159,47 @@ init: ldx #zpspace-1
lda #>_exit lda #>_exit
jsr reset ; Setup RESET vector jsr reset ; Setup RESET vector
; Setup the stack ; Check for ProDOS
lda HIMEM ldy $BF00 ; MLI call entry point
sta sp cpy #$4C ; Is MLI present? (JMP opcode)
lda HIMEM+1 bne basic
sta sp+1 ; Set argument stack ptr
; Check ProDOS system bit map
lda $BF6F ; protection for pages $B8 - $BF
cmp #%00000001 ; exactly page $BF is protected
bne basic
; No BASIC.SYSTEM so quit to ProDOS dispatcher instead
lda #<quit
ldx #>quit
sta done
stx done+1
; No BASIC.SYSTEM so use addr of ProDOS system global page
lda #<$BF00
ldx #>$BF00
bne :+ ; Branch always
; Get highest available mem addr from BASIC interpreter
basic: lda HIMEM
ldx HIMEM+1
; Setup the C stack
: sta sp
stx sp+1
; Check for interruptors ; Check for interruptors
lda #<__INTERRUPTOR_COUNT__ lda #<__INTERRUPTOR_COUNT__
beq :+ beq :+
; Check for ProDOS ; Check for ProDOS
lda $BF00 ; MLI call entry point cpy #$4C ; Is MLI present? (JMP opcode)
cmp #$4C ; Is MLI present? (JMP opcode)
bne prterr bne prterr
; Allocate interrupt vector table entry ; Allocate interrupt vector table entry
jsr $BF00 ; MLI call entry point jsr $BF00 ; MLI call entry point
.byte $40 ; Alloc interrupt .byte $40 ; Alloc interrupt
.addr params .addr i_param
bcs prterr bcs prterr
; Enable interrupts as old ProDOS versions (i.e. 1.1.1) ; Enable interrupts as old ProDOS versions (i.e. 1.1.1)
@ -223,7 +245,7 @@ msglen = * - errmsg
; ProDOS TechRefMan, chapter 6.2: ; ProDOS TechRefMan, chapter 6.2:
; "Each installed routine must begin with a CLD instruction." ; "Each installed routine must begin with a CLD instruction."
intrpt: cld intptr: cld
; Call interruptors and check for success ; Call interruptors and check for success
jsr callirq jsr callirq
@ -248,13 +270,33 @@ reset: stx SOFTEV
sta PWREDUP sta PWREDUP
rts rts
; Quit to ProDOS dispatcher
quit: jsr $BF00 ; MLI call entry point
.byte $65 ; Quit
.word q_param
; ------------------------------------------------------------------------
.rodata
; MLI parameter list for quit
q_param:.byte $04 ; param_count
.byte $00 ; quit_type
.word $0000 ; reserved
.byte $00 ; reserved
.word $0000 ; reserved
; ------------------------------------------------------------------------ ; ------------------------------------------------------------------------
.data .data
params: .byte $02 ; Parameter count ; MLI parameter list for (de)alloc interrupt
intnum: .byte $00 ; Interrupt number i_param:.byte $02 ; param_count
.addr intrpt ; Interrupt handler int_num:.byte $00 ; int_num
.addr intptr ; int_code
; Location to jump to when we're done
done: .addr DOSWARM
; ------------------------------------------------------------------------ ; ------------------------------------------------------------------------