Apple Disk Transfer 1.22
by Paul Guertin
pg@sff.net
December 4th, 1995 - 1999
Apple II <==> MS-DOS
Apple Disk Transfer (ADT for short) is a set of two programs to
transfer a standard 16-sector Apple II disk to a 140k file on an
MS-DOS computer, and transfer a standard disk image file to disk
on an Apple II.
ADT 1.22 requires the Apple II to have a Super Serial Card, a card
which is hardware-compatible with SSC, or built-in SSC-compatible
serial port hardware. The IIc+ and //c include SSC-compatible
serial ports. The built-in IIgs serial ports are _not_ hardware-
compatible with SSC and will not work with ADT 1.22.
ADT is freeware.
* * *
Contents of ADT122.ZIP archive:
readme.txt -- This file.
adt122.dsk -- Disk image containing ADT 1.22 (see below).
APPLE II FILES:
adt.asm -- Source code for ADT (Merlin assembler).
adt.dmp -- Object code for ADT (Monitor dump format).
adtcfg.bas -- Applesoft program to configure ADT.
MS-DOS FILES:
adt.exe -- MS-DOS executable.
adt.c -- Source code for adt.exe (Turbo C 2.0).
comm.c -- Freeware serial port routines for Turbo C.
comm.h -- Header file for above.
* * *
What's new in version 1.22:
1. Modified "About" message and docs.
2. Otherwise; no changes.
What was new in version 1.21:
1. If a sector can't be read, it will be filled with zeros
instead of keeping the old data of 7 tracks ago.
2. Changed "int be" to "unsigned be" in comm_open(). Thanks
to Tim G. Foley <timf@interlog.com> for pointing out this
bug.
What was new in version 1.20:
1. Added a configuration menu with user-selectable number
of retries, etc.
2. Added a "Dir" function to see the contents of the current
MS-DOS directory.
3. You can now push Escape at any time to abort a transfer.
4. In previous versions, a bug made ADT retry 256 times if
there was more than one bad sector in a 7-track block.
Fixed.
5. Faster CRC calculations.
6. Some cosmetic changes, better error messages. The usual
stuff you find in a minor revision.
What was new in version 1.11:
1. In version 1.10, I forgot to set IOBVOL to 0 before calling
RWTS, resulting in spurious "Not a 16-sector disk" errors.
Fixed.
What was new in version 1.10:
1. ADT now uses a simple compression scheme (differential run
length encoding) that will speed up the transfer of many
disks.
2. 16-bit CRC error detection for each sector.
3. ADT now tries 5 times to get a good read instead of giving
up at the first error. This may help transferring old,
flaky disks.
4. The transfer speed is now always 19200 bps.
What was new in version 1.01:
1. Bug fix: 12-character (8.3) MS-DOS filenames now accepted.
2. Serial card initialization did not work with some serial
cards.
* * *
For those upgrading from a previous version of ADT:
Just format a blank disk on your Apple II and use your current ADT
to transfer the file ADT.DSK. This disk image contains ADT (the
executable program), ADT.ASM (source code), and ADT CONFIGURATION.
On the MS-DOS side, replace your current ADT.EXE with the new one
from the .zip archive.
* * *
Installation:
You will need a null-modem cable to connect the PC and the Apple II.
If you don't have one, you can make your own (see the end of this
file) or buy one at your local computer store.
Note: if you have a genuine Apple Super Serial Card, you do not need a
null modem cable. Simply set the jumper on the card to "terminal"
rather than "modem", and use a standard "straight-through" cable.
Thanks to Greg Bennett for this tip.
To install ADT on the PC: there's nothing special to do, since you've
already unzipped ADT122.ZIP. The executable file is called ADT.EXE.
To install ADT on the Apple II: Boot a DOS 3.3 disk with some free
space, and from BASIC type IN#x, where x is the slot your serial card
is in (typically, x=2). Set the speed to 300 baud by typing the
three characters "<ctrl-A>6B".
Then, on the PC, start a comm program, set it for 300 baud N81, and
ASCII-upload (not Xmodem or any other protocol but a straight text
upload) the file "adt.dmp" to the Apple. (Example: Using HyperTerm
Under Windows 95, you would Send Text.)
During the transfer process, the program will enter itself into
the Monitor and save itself to disk under the name "ADT". Here are
some tips to get this to work. If nothing seems to work, you can
always type in the hex dump by hand (yep, it's getting longer with
each new version, but it's still under 2.5k).
1. If you get a beep at every line, the PC comm program is
probably sending CRLFs to your Apple, which only likes
CRs. Turn on the "Strip linefeeds on output" option in
your comm program.
2. If you see total garbage on the Apple II screen, first be
sure that the SSC and the comm program agree on the
transfer speed. If they do, your comm program is probably
doing something funny with the high bit (aka bit 7) of
each character. Turn off the "Strip high bit on output"
option.
3. If you are uploading ADT to an unaccelerated Apple II,
you may need to slow down the transfer. Your comm program
probably allows you to set a fixed delay between each
line (aka "line pacing"). A 1.2-second pause worked well
with a 1 MHz Apple //c. [Note: disk transfers with ADT
are done at 19200 bps, even with a 1 MHz machine. The
slowness here is due to the way the Apple Monitor works.]
Now, make sure your Apple is in BASIC and ASCII-upload the file
"adtcfg.bas". Again, the program will enter itself and be saved to
disk under the name "ADT CONFIGURE". Since BASIC has to parse each
line after it has been entered, you will probably need to increase the
"line pacing" value. Just to be sure it will work, I set it to 3
seconds.
* * *
How to use ADT:
On the Apple II, type 'BRUN ADT' from the DOS 3.3 prompt. On the PC,
you can type 'ADT', and the program will ask you which serial port to
use and the transfer speed. You can also type these parameters on the
MS-DOS command line, eg. 'ADT 2 19200'. If you always use the same
serial port and speed, I suggest making a batch file or a 4DOS alias.
Except for the PC configuration (serial port & speed), ADT operation
is entirely controlled from the Apple II keyboard, so you can transfer
many disks without having to go back and forth between the two
computers.
At the bottom of the Apple screen, you will see the following menu:
Send, Receive, Dir, Configure, Quit?
To select an item, simply type the first letter of the word. One
keystroke is enough, you don't have to hit Return.
Send: ADT will ask for an MS-DOS filename and then start reading the
disk in the specified slot and drive and transmit it to the PC, which
will store it in that file. ADT will not overwrite an existing file.
All files are stored in the current directory and are 143,360 bytes
in length.
The MS-DOS file format is as follows:
T0S0B0 T0S0B1 ... T0S0BFF T0S1B0 ... ... T22SFBFF
which is the format used by the apl2em emulator by Randy Spurlock.
Receive: ADT will ask for a filename. It will then receive that file
from the PC's current directory and write it to the disk in slot 6
drive 1, overwriting any data that may be on the disk. THE DISK IN
SLOT 6 DRIVE 1 MUST BE 16-SECTOR FORMATTED. Before transmitting, ADT
ensures that the file exists and is 140k in length. (I didn't add
signature bytes because I wanted to stay compatible with the apl2em
format.)
Dir: ADT will display a list of the files in the current MS-DOS
directory. There is currently no way to change directories from within
ADT.
Configure: this takes you to the ADT configuration menu. Use the up
and down arrow keys to select a parameter (Apple ][+ users, use space
instead). The left and right arrow keys change the value of the
current parameter. Return saves the displayed values and exits. Escape
exits without saving the changes. Finally, ctrl-D resets all
parameters to the default values (you can change the default values by
using the BASIC program ADT CONFIGURATION). Here's an explanation of
each parameter:
Disk slot, disk drive, SSC slot: self-explanatory. The
defaults are slot 6, drive 1, and the SSC in slot 2.
SSC speed: use the highest speed that works. The default is
19200, and it works with my 1 MHz Apple //e.
Read retries: number of times RWTS will try to read a sector
before giving up. I suggest 1 or 2. If you have a
particularly weak disk, and don't mind the recalibrating
noise, you can increase it (also consider adjusting your
drive speed, and cleaning the drive head).
Write retries: same, but for writing to a disk. The default
is 0: if I have trouble writing to a disk, even only once, I
usually trash the disk. My data is worth more than $0.50.
Use checksums: DOS puts a checksum at the end of each sector
as an error-detection measure. If the checksum is wrong, it
means the data is probably corrupt and RWTS will issue an I/O
error. Setting this parameter to NO will defeat this check:
even if the checksum is wrong, the sector will be read
normally. This may be of some help in transferring very old
disks on which a few bits have . It will also allow ADT to
copy disks where the only protection scheme is a different
checksum algorithm.
When you modify this parameter, ADT patches the copy of
DOS in memory. If you're using a non-standard version of DOS,
the code that checks for checksum errors may have been moved
to a different address. In that case, ADT will show the words
"DO NOT CHANGE" next to the parameter. (It will not prevent
you from changing it, however... If you really want to
overwrite two random bytes in your custom DOS, go ahead, but
you assume all the risks!)
This parameter was suggested by Andy McFadden.
Enable sounds: YES means ADT will beep when a transfer is
finished, and on some other occasions. If this parameter is
set to NO, ADT will be totally silent. By the way, some of
you old-timers may recognize the beep: it's the same beep
used in my all-time favorite word processor, Apple Writer II
by Paul Lutus.
Quit: This quits ADT, returning to DOS 3.3.
?: Shows "About ADT" message.
On the PC, you can type the following keys:
C allows you to change the serial port and speed (if you
change the speed on one computer, don't forget to do the same
for the other).
ctrl-L redraws the screen.
Q quits ADT.
Even though ADT runs under DOS 3.3, it will also transfer ProDOS disks
as well as Pascal disks, because they are all in 16-sector format.
On the PC, a disk will always arrive as a DOS 3.3 ordered .dsk disk
image file. You should include ".dsk" at the end of the name for any
disk you send or add ".dsk" to the file name on the PC.
On the Apple II, a transferred .dsk disk image file is converted
directly to 5.25" diskette.
ADT will not transfer DOS 3.2 (13-sector) disks to PC; and, It will not
transfer protected disks to PC unless the protection scheme is based on
the DOS checksums only (and even then, there's no guarantee the disk will
work in the emulator).
ADT will not correctly transfer ProDOS-order (.po) disk image files to
the Apple II.
Meaning of characters on the Apple II status display:
R: Reading from disk
W: Writing to disk
I: Receiving data from PC ("Input")
O: Sending data to PC ("Output")
.: Sector read or written correctly
*: Error while reading or writing sector
ABORTING: You can press the escape key at any time during the transfer
and everything will stop. You will be back to the ADT menu. This is
true for the Apple and the PC. When you are aborting a transfer, stop
the _sending_ computer first. If you first stop the receiving
computer, it will continue to receive unexpected data and may become
confused.
ADT CONFIGURATION: use this BASIC program to change the default
parameter values. Its operation is self-explanatory. Just follow
the prompts.
* * *
Speed comparison for ADT 1.01, 1.11, and 1.22 (Apple to PC, 19200 bps)
Disk 1.01 1.11 1.22
------------------------- ---- ---- ----
DOS 3.3 System Master: 1:42 1:33 0:59 (times are min:sec)
AW data disk, 1k free: 1:42 2:13 1:30
Eamon adventure #12: 1:42 1:24 0:48
Karateka (cracked): 1:42 1:54 1:15
1.01 always takes 1:42 since it does not use a compression algorithm.
1.11 does RLE compression and CRC error checking (this explains why it
is sometimes slower than 1.01).
1.22 also does RLE and has a faster CRC routine.
* * *
Recompilation / reassembly:
On the PC: to compile ADT with Turbo C 2.0, use: "TCC ADT.C COMM.C".
Recompilation is required only if you modify the program.
On the Apple II: ADT doesn't use any esoteric Merlin-specific
pseudo-opcodes or macros and should be easy to port to other
assemblers.
* * *
ADT is based on the program SENDDISK by Rich Williamson
(glitch@eskimo.com). In fact, version 0.01 of ADT was a patch to
SENDDISK to make it transfer files from the PC to the Apple. I wish
to acknowledge Mr. Williamson's contribution to ADT.
* * *
The following is taken from the SENDDISK readme file, and may
help you configure your hardware.
> Super Serial card DIP settings: (19200 baud)
> SW1-1 off SW2-1 on
> 1-2 off 2-2 on
> 1-3 off 2-3 off
> 1-4 off 2-4 on
> 1-5 on 2-5 off
> 1-6 on 2-6 off
> 1-7 on 2-7 off
>
> Put the TERMINAL/MODEM jumper pointing up at 'MODEM'
>
> Serial cable wiring
> PC (DB-9) Apple (DB-25)
>
> 2 - 2
> 3 - 3
> 4 - 8
> 5 - 7
* * *
I welcome comments, bug reports, suggestions for future versions, etc.
Send fan mail to pg@sff.net.
=EOF=