Re: Disk Image to cassette tape

[TWS <adoyson@nccn.net>]

TAPESAVE is not a Dos or Prodos command  (although, I think that there is a command from
DOS 3.3 that will save/load to tape)

To SAVE/LOAD to tape,  you have to use the MONITOR commands.  From the BASIC/DOS prompt,
type:

]CALL-151                         to get to the MONITOR


Hmmm.  Looking through My  Apple II Reference Manual.

*******************************************************
Saving a range of memory on tape

The Monitor has 2 special commands which allow you to save a range of memory onto
cassette tape and recall it again for later use.  The first of these 2 commands, WRITE,
lets you save the  contents of one to 65,536 memory locations on standard cassette tape

Top save a range of memory to tape, give the Monitor the starting and ending addresses
of the range, followed by the letter W (for WRITE)

{start} . {end} W

To get an accurate recording, you should put the tape recorder in RECORD mode befvore
you press RETURN on the input line.  Let the tape run a few seconds, then press RETURN.
The Monitor will write a ten-second "leader" tone onto the tape, followed by the data.
When the Monitor is finished, it will sound a "bep!"  and give you another prompt.  You
should then rewind the tape, and label the tape with something intelligible about the
memory range that's on the tape and what it's supposed to be

*0.FF  FF AD 30 C0 88 D0 04 C6 01 F0 08 CA D0 F6 A6 00 00 4C 02 00 60
*0.14

0000-FF FF AD 30 C0 88 D0 04
0008-C6 01 F0 08 CA D0 F6 A6
0010-00 4C 02 00 60

*0.14W

It takes about 35 seconds total to save the values of 4096 memory locations preceded by
the ten-second leader onto tape.  This works out to a speed of about 1350 bits per
second, average.  The WRITE command writes one extra value on the tape after it has
written the values in the memory range.  This extra value is the Checksum.  It is the
partial sum of all values in the range.  The READ subroutine uses this value to
determine if a READ has been successful (see below)
***********************************************************

So, you'd need to use a Disk-to-DiskImage utility to turn a disk into a file, chop it
into a few chunks so It will fit in Apple II memory, then send each chunk over the
Cassette output.

I'll  type the rest of it later.  Basically, use the {start}.{end}R command   (start is
the beginning memory location you want to load to)

"ERR" will appear on the screen if a READ was not successful

Sandy


Sean Burnett wrote:

> Hi,
> I just ran a couple tests using the SAVE command to dump it from memory
> to cassette out and it's looking quite feasible, space-wise.  An entire
> disk volume would take about 8.5 minutes.  It's slow, but not
> unreasonable, so neither would the harddrive space as a .wav file.  I
> believe I can keep the audio file of a disk image under 2MB and still
> keep the resolution needed for safe transfer.  I'm going to go ahead and
> write the audio file -> bit stream process (batch).  That'll be fun.
> I'm not sure if the TAPESAVE routine puts in stop bits or what the
> header or trailer consists of, but I guess I'll find out.
>
> If you could send me the utility that you mentioned, that would be
> great.  Are you able to send it to me as a .wav file?  I know that
> sounds crazy (and is asking a lot), but I have no other way of loading a
> program coming from the internet.  I would just play the .wav file from
> my sound card into the cassette in.
>
> Also, you mentioned a TAPESAVE command.  I tried it but it did not work.
> Is it a PRODOS command?  Perhaps I just didn't use the correct syntax.
>
> Geez, I'm sure requesting a lot of stuff.  I won't be offended if it's
> too much hassle.
>
> Thanks for all your comments/suggestions!
>
> TWS wrote:
> >
> > Hi,
> >
> > How about this.  Use a Disk to DiskImage converter to convert your disk on the
> > Apple II.   Connect your Apple II Cass OUT to your PC's SOUNDBLASTER (or Macintosh
> > Sound)  INPUT.  Use the ROM in the Apple (there is a TAPESAVE command) to save the
> > 143k disk image over the CASSETTE port.  Press RECORD on the Mac/IBM sound
> > recording program.
> >
> > Write a program for you IBM (or Mac?) that will decode the Audio into a binary
> > file.  The program would involve some Timing loops to synchronize with the sound
> > file.  Shouldn't be hard at all.
> >
> > Problems you could have:  #1  a 143k sound file sent from the Apple II cassette
> > port may be 4 hours long.  I don't know how long it will be.  Do you really want a
> > 4Hour long sound file on your Mac/Pc Hard drive?
> >
> > Hmm how about writing a program for your IBM/Mac that will Get sound from the
> > AUDIO INPUT, and De-code it into data as it receives the sound?
> >
> > Sean Burnett wrote:
> >
> > > Hi,
> > > Thank you for the responses, everybody.  This is the best newsgroup I've
> > > had the opportunity to follow.  No major attitudes or anything, and
> > > everybody seems very helpful.  Enough of the touchy feely stuff - now
> > > down to business.
> > >
> > > My goal in asking the 'cassette out' question is that I hope to be able
> > > to do this:
> > >         1) write a disk image to tape (actually, minidisc track)
> > >         2) transfer this to a more modern computer into a .wav file
> > >         3) write a program to extract the Apple ][e disk image out of the .wav
> > > file.
> > >
> > > My first project will be to do a single Apple file and use DSK_OUT to
> > > convert it to a disk image for use in an emulator.
> > >
> > > There seems to be mechanisms for getting Apple ][e disk images if
> > > someone has a serial port or compatible game port and cable, but not
> > > using the cassette out peripheral.
> > >
> > > Any comments?  Would this be a worthwhile endeavour for anybody except
> > > me?  Any rate, it will be a good exercise.  I will post the program when
> > > it is complete.
> > >
> > > Sir Cain wrote:
> > > >
> > > > I had a program called COS (Cassette Operating System), I think, that came
> > > > on an old Micro disk.  It would break up an Disk image into four or five
> > > > parts and save them to cassette (or restore from cassette to disk).  It was
> > > > not a complete Operating System, but more like a utility program.  And of
> > > > course it was slow.  I'd give more specific info, but I've recently moved
> > > > and all my old computer books (and software) are still in boxes.
> > > >
> > > > Greg Buchner wrote in message ...
> > > > >In article <3622A3F5.D7702F72@swbell.net>, rubywand@swbell.net wrote:
> > > > >
> > > > >>     Is it possible to save a 140kb disk image to cassette? Yes; but,
> > > > >>you would need to break up the image file into smaller pieces. One idea
> > > > >>is to add your own routines to do something like read chunks of the disk
> > > > >>image file (perhaps 4096 bytes per chunk) and write the data to tape.
> > > > >>Then you would need a Big File tape read routine to read the chunks and
> > > > >>put them on disk.
> > > > >
> > > > >I at one time did have a program, was probably DOS 3.3 that did copy
> > > > >disks back and forth to the tape drive.  I seem to remember that it was
> > > > >supposed to be able to fit five disks on one side of a 90 minute tape.
> > > > >
> > > > >This was probably twelve years ago and that's all that I remember about
> > > > >it.  Never used it, so can't be certain about any of this.
> > > > >
> > > > >Greg B.
> > > > >
> > > > >--
> > > > >*****
> > > > >Note:  To e-mail me, replace someone with gjb
> > > > >I don't get junk e-mail and intend to keep it that way.