mirror of
https://github.com/deater/dos33fsprogs.git
synced 2024-12-26 11:30:12 +00:00
297 lines
5.5 KiB
ArmAsm
297 lines
5.5 KiB
ArmAsm
; File I/O routines based on sample code in
|
|
; "Beneath Apple DOS" by Don Worth and Pieter Lechner
|
|
|
|
;; For the disk-read code
|
|
;RWTSL EQU $F0
|
|
;RWTSH EQU $F1
|
|
;DOSBUFL EQU $EE
|
|
;DOSBUFH EQU $EF
|
|
;FILEML EQU $EC
|
|
;FILEMH EQU $ED
|
|
|
|
|
|
;; DOS Constants
|
|
OPEN EQU $01
|
|
CLOSE EQU $02
|
|
READ EQU $03
|
|
WRITE EQU $04
|
|
DELETE EQU $05
|
|
CATALOG EQU $06
|
|
LOCK EQU $07
|
|
UNLOCK EQU $08
|
|
RENAME EQU $09
|
|
POSITION EQU $0A
|
|
INIT EQU $0B
|
|
VERIFY EQU $0C
|
|
|
|
LOCATE_FILEM_PARAM EQU $3DC
|
|
LOCATE_RWTS_PARAM EQU $3E3
|
|
FILEMANAGER EQU $3D6
|
|
|
|
|
|
;================================
|
|
; read from disk
|
|
;================================
|
|
; FILENAME pointed to by INH:INL
|
|
; OUTH:OUTL trashed
|
|
; output buffer: disk_buff
|
|
; size to read: read_size
|
|
|
|
read_file:
|
|
jsr LOCATE_FILEM_PARAM ; $3DC entry point
|
|
; load file manager param list
|
|
; returns Y=low A=high
|
|
|
|
sta FILEMH
|
|
sty FILEML
|
|
|
|
; ldy #7 ; file type offset = 7
|
|
; lda #0 ; 0 = text
|
|
; sta (FILEML),y
|
|
|
|
|
|
; copy filename into place
|
|
ldy #0
|
|
lda #<filename ; combine with below? (filename-8?)
|
|
sta OUTL
|
|
lda #>filename
|
|
sta OUTH
|
|
|
|
filename_copy_loop:
|
|
lda (INL),y ; load byte
|
|
beq filename_pad_spaces ; if zero, done
|
|
ora #$80 ; convert to apple ascii
|
|
sta (OUTL),y ; store out
|
|
iny
|
|
bne filename_copy_loop
|
|
|
|
filename_pad_spaces:
|
|
lda #$A0 ; filename needs ' ' padded
|
|
sta (OUTL),y
|
|
iny
|
|
cpy #30 ; fill 30 bytes
|
|
bne filename_pad_spaces
|
|
|
|
filename_pad_done:
|
|
|
|
ldy #8 ; filename ptr offset = 8
|
|
lda #<filename
|
|
sta (FILEML),y
|
|
iny
|
|
lda #>filename
|
|
sta (FILEML),y
|
|
|
|
ldx #1 ; open existing file
|
|
|
|
jsr dos33_open ; open file
|
|
bcs error_open
|
|
|
|
jsr dos33_read ; read buffer
|
|
bcc now_close
|
|
; got an error
|
|
; error 05 is OK (OUT OF DATA)
|
|
; because we try to read too much
|
|
ldy #$a
|
|
lda (FILEML),Y
|
|
cmp #5
|
|
beq now_close
|
|
|
|
jmp error_read
|
|
|
|
now_close:
|
|
jsr dos33_close ; close file
|
|
bcs error_close
|
|
|
|
rts
|
|
|
|
error_open:
|
|
lda #$f5
|
|
brk
|
|
error_read:
|
|
ldy #$a
|
|
lda (FILEML),y
|
|
tay
|
|
lda #$f6
|
|
brk
|
|
error_close:
|
|
lda #$f7
|
|
brk
|
|
|
|
;=================================
|
|
; get_dos_buffer
|
|
;=================================
|
|
;
|
|
; Dos buffer format
|
|
; 0x000-0x0ff = data buffer
|
|
; 0x100-0x1ff = t/s list buffer
|
|
; 0x200-0x22c = file manager workarea (45 bytes)
|
|
; 0x22d-0x24a = file name buffer
|
|
|
|
; 0x24b-0x24c = address of file manager workarea
|
|
; 0x24d-0x24e = address of t/s list buffer
|
|
; 0x24f-0x250 = adress of data sector buffer
|
|
; 0x251-0x252 = address of file name field for the next buffer
|
|
|
|
; In DOS, $3D2 points to 0x22d of first buffer
|
|
; add 0x24 to get chain pointer
|
|
|
|
|
|
dos33_open:
|
|
; allocate one of the DOS buffers so we don't have to set them up
|
|
|
|
allocate_dos_buffer:
|
|
lda $3D2 ; DOS load point
|
|
sta DOSBUFH
|
|
ldy #0
|
|
sty DOSBUFL
|
|
|
|
buf_loop:
|
|
lda (DOSBUFL),Y ; locate next buffer
|
|
pha ; push on stack
|
|
; we need this later
|
|
; to test validity
|
|
|
|
iny ; increment y
|
|
lda (DOSBUFL),Y ; load next byte
|
|
sta DOSBUFH ; store to buffer pointerl
|
|
|
|
pla ; restore value from stack
|
|
|
|
sta DOSBUFL ; store to buffer pointerh
|
|
|
|
bne found_buffer ; if not zero, found a buffer
|
|
|
|
lda DOSBUFH ; also if not zero, found a buffer
|
|
bne found_buffer ; no buffer found, exit
|
|
|
|
sec ; failed
|
|
|
|
rts
|
|
|
|
found_buffer:
|
|
ldy #0 ; get filename
|
|
lda (DOSBUFL),Y ; get first byte
|
|
beq good_buffer ; if zero, good buffer
|
|
|
|
; in use
|
|
ldy #$24 ; point to next
|
|
bne buf_loop ; and loop
|
|
|
|
good_buffer:
|
|
lda #$78
|
|
sta (DOSBUFL),Y ; mark as in use (can be any !0)
|
|
|
|
keep_opening:
|
|
ldy #0
|
|
lda #OPEN ; set operation code to OPEN
|
|
sta (FILEML),y
|
|
|
|
ldy #2 ; point to record length
|
|
lda #0 ; set it to zero (16-bits)
|
|
sta (FILEML),y
|
|
iny
|
|
sta (FILEML),y
|
|
|
|
iny ; point to volume num (0=any)
|
|
sta (FILEML),y
|
|
|
|
jsr LOCATE_RWTS_PARAM ; get current RWTS parameters
|
|
; so we can get disk/slot info
|
|
|
|
sty RWTSL
|
|
sta RWTSH
|
|
|
|
ldy #1
|
|
lda (RWTSL),y ; get slot*16
|
|
lsr a
|
|
lsr a
|
|
lsr a
|
|
lsr a ; divide by 16
|
|
|
|
ldy #6 ; address of slot
|
|
sta (FILEML),y ; store it
|
|
|
|
ldy #2
|
|
lda (RWTSL),y ; get drive
|
|
ldy #5 ; address of drive
|
|
sta (FILEML),y
|
|
|
|
filemanager_interface:
|
|
|
|
ldy #$1E
|
|
dbuf_loop:
|
|
lda (DOSBUFL),y ; get three buffer pointers
|
|
pha ; push onto stack
|
|
iny ; increment pointer
|
|
cpy #$24 ; have we incremented 6 times?
|
|
bcc dbuf_loop ; if not, loop
|
|
|
|
ldy #$11 ; point to the end of the same struct
|
|
; in file manager
|
|
fmgr_loop:
|
|
pla ; pop value
|
|
sta (FILEML),Y ; store it
|
|
dey ; work backwards
|
|
cpy #$c ; see if we are done
|
|
bcs fmgr_loop ; loop
|
|
|
|
jmp FILEMANAGER ; #3D6
|
|
; run filemanager
|
|
; will return for us
|
|
|
|
;====================
|
|
; close DOS file
|
|
;====================
|
|
|
|
dos33_close:
|
|
ldy #0 ; command offset
|
|
lda #CLOSE ; load close
|
|
sta (FILEML),y
|
|
|
|
jsr filemanager_interface
|
|
bcs error_close
|
|
|
|
ldy #0 ; mark dos buffer as free again
|
|
tya
|
|
sta (DOSBUFL),y
|
|
|
|
rts
|
|
|
|
;=========================
|
|
; read from dos file
|
|
;=========================
|
|
|
|
dos33_read:
|
|
ldy #0 ; command offset
|
|
lda #READ
|
|
sta (FILEML),y
|
|
|
|
iny ; point to sub-opcode
|
|
lda #2 ; "range of bytes"
|
|
sta (FILEML),y
|
|
|
|
ldy #6 ; point to number of bytes to read
|
|
lda #<read_size
|
|
sta (FILEML),y ; we want to read read_size bytes
|
|
iny
|
|
lda #>read_size
|
|
sta (FILEML),y
|
|
|
|
ldy #8 ; buffer address
|
|
lda #<disk_buff
|
|
sta (FILEML),y
|
|
iny
|
|
lda #>disk_buff
|
|
sta (FILEML),y
|
|
|
|
jmp filemanager_interface
|
|
|
|
filename:
|
|
; OUT.0
|
|
.byte 'I'+$80,'N'+$80,'T'+$80,'R'+$80,'O'+$80
|
|
.byte '2'+$80,'.'+$80,'K'+$80,'R'+$80,'W'+$80
|
|
.byte $A0,$A0,$A0,$A0,$A0
|
|
.byte $A0,$A0,$A0,$A0,$A0
|
|
.byte $A0,$A0,$A0,$A0,$A0
|
|
.byte $A0,$A0,$A0,$A0,$A0
|