mirror of
https://github.com/cc65/cc65.git
synced 2024-06-28 03:29:39 +00:00
6d498d8187
to emulate these functions on platforms where one or more of these functions are not available (PET, CBM-II). git-svn-id: svn://svn.cc65.org/cc65/trunk@1544 b7a2c559-68d2-44c3-8de9-860c34a00d81
215 lines
5.5 KiB
ArmAsm
215 lines
5.5 KiB
ArmAsm
;
|
|
; Ullrich von Bassewitz, 17.11.2002
|
|
;
|
|
; Handle disk command channels
|
|
;
|
|
|
|
.export isdisk
|
|
.export opencmdchannel
|
|
.export closecmdchannel
|
|
.export readdiskerror
|
|
.export writediskcmd
|
|
|
|
.import SETLFS, SETNAM, OPEN, CLOSE, BSOUT, BASIN
|
|
.import CHKIN, CKOUT, CLRCH
|
|
.importzp tmp1, ptr1
|
|
|
|
.include "cbm.inc"
|
|
.include "filedes.inc"
|
|
|
|
;--------------------------------------------------------------------------
|
|
; isdisk: Return carry clear if the unit number in X is a disk, return
|
|
; carry set if not.
|
|
|
|
.proc isdisk
|
|
|
|
cpx #FIRST_DRIVE ; Disk unit?
|
|
bcc @L1 ; Branch if no disk
|
|
cpx #FIRST_DRIVE+MAX_DRIVES
|
|
rts
|
|
|
|
@L1: sec
|
|
rts
|
|
|
|
.endproc
|
|
|
|
;--------------------------------------------------------------------------
|
|
; Open the command channel for the disk unit in X. The function returns an
|
|
; error code in A and sets the flags according to the contents of A.
|
|
|
|
opencmdchannel:
|
|
|
|
jsr isdisk ; Disk unit?
|
|
bcs success
|
|
|
|
; Is this channel already open?
|
|
|
|
ldy opentab-FIRST_DRIVE,x
|
|
bne isopen
|
|
|
|
; Open the command channel, Carry is still clear
|
|
|
|
stx tmp1 ; Save the unit number
|
|
txa ; Get unit number
|
|
adc #(LFN_OFFS+MAX_FDS-FIRST_DRIVE)
|
|
ldy #15 ; Secondary address for cmd channel
|
|
jsr SETLFS
|
|
|
|
lda #0
|
|
jsr SETNAM ; No name supplied to OPEN
|
|
|
|
jsr OPEN
|
|
bcs done ; Error, code is in A
|
|
|
|
; Command channel is open now. Increment the count
|
|
|
|
ldx tmp1 ; Unit number
|
|
ldy opentab-FIRST_DRIVE,x
|
|
isopen: iny
|
|
tya
|
|
sta opentab-FIRST_DRIVE,x
|
|
|
|
; Done, return success
|
|
|
|
success:lda #$00
|
|
done: cmp #$00 ; Set flags for return code
|
|
rts
|
|
|
|
|
|
;--------------------------------------------------------------------------
|
|
; closecmdchannel: Decrement the counter for the disk command channel and
|
|
; close the channel if the counter drops to zero. The function expects the
|
|
; drive number in X and returns an error code in A. The flags for the return
|
|
; code are set when the function returns.
|
|
|
|
closecmdchannel:
|
|
|
|
jsr isdisk ; Disk unit?
|
|
bcs success
|
|
|
|
; Is this channel really open?
|
|
|
|
ldy opentab-FIRST_DRIVE,x
|
|
beq success ; OOPS! Channel is not open
|
|
|
|
; Decrement the count and stor it back
|
|
|
|
dey
|
|
tya
|
|
sta opentab-FIRST_DRIVE,x
|
|
|
|
; If the counter is now zero, close the channel. We still have carry clear
|
|
; when we come here.
|
|
|
|
bne success
|
|
txa ; Make LFN from drive number
|
|
adc #(LFN_OFFS+MAX_FDS-FIRST_DRIVE)
|
|
jsr CLOSE
|
|
bcs done
|
|
bcc success
|
|
|
|
;--------------------------------------------------------------------------
|
|
; readdiskerror: Read a disk error from an already open command channel.
|
|
; Returns an error code in A, which may either be the code read from the
|
|
; command channel, or another error when accessing the command channel failed.
|
|
|
|
readdiskerror:
|
|
|
|
jsr isdisk
|
|
bcs success
|
|
|
|
; Read the command channel. We won't check the status after the channel is
|
|
; open, because this seems to be unnecessary in most cases.
|
|
|
|
txa
|
|
clc ; Make LFN from drive number
|
|
adc #(LFN_OFFS+MAX_FDS-FIRST_DRIVE)
|
|
tax
|
|
jsr CHKIN ; Make the command channel input
|
|
bcs done ; Bail out with error code in A
|
|
|
|
jsr BASIN
|
|
and #$0F ; Make digit value from PETSCII
|
|
sta tmp1
|
|
asl a ; * 2
|
|
asl a ; * 4, carry clear
|
|
adc tmp1 ; * 5
|
|
asl a ; * 10
|
|
sta tmp1
|
|
|
|
jsr BASIN
|
|
and #$0F ; Make digit value from PETSCII
|
|
clc
|
|
adc tmp1
|
|
|
|
; Errors below 20 are not real errors. Fix that
|
|
|
|
cmp #20+1
|
|
bcs @L1
|
|
lda #$00
|
|
@L1: pha
|
|
|
|
; Read the remainder of the message and throw it away
|
|
|
|
@L2: jsr BASIN
|
|
cmp #$0D
|
|
bne @L2
|
|
|
|
; Close the input channel
|
|
|
|
jsr CLRCH
|
|
|
|
; Restore the error code (will also set the flags) and return
|
|
|
|
pla
|
|
rts
|
|
|
|
;--------------------------------------------------------------------------
|
|
; writediskcmd: Gets pointer to data in ptr1, length in A. Writes all data
|
|
; to the command channel of the given drive. Returns an error code in A,
|
|
; flags are set according to the contents of A.
|
|
|
|
writediskcmd:
|
|
|
|
jsr isdisk
|
|
bcs success
|
|
|
|
; Remember the length
|
|
|
|
sta tmp1
|
|
|
|
; Write to the command channel.
|
|
|
|
txa
|
|
clc ; Make LFN from drive number
|
|
adc #(LFN_OFFS+MAX_FDS-FIRST_DRIVE)
|
|
tax
|
|
jsr CKOUT ; Make the command channel output
|
|
bcs done ; Bail out with error code in A
|
|
|
|
ldy #$00
|
|
@L1: cpy tmp1
|
|
bcs @L3
|
|
lda (ptr1),y
|
|
iny
|
|
jsr BSOUT
|
|
bcc @L1
|
|
|
|
@L2: pha
|
|
jsr CLRCH
|
|
pla
|
|
rts
|
|
|
|
@L3: jsr CLRCH
|
|
lda #$00
|
|
rts
|
|
|
|
|
|
|
|
;--------------------------------------------------------------------------
|
|
; Data
|
|
|
|
.bss
|
|
|
|
opentab: .res MAX_DRIVES, 0
|