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Re: Cassette images?



Sir Morris wrote:
Many thanks everyone - it's good to discover a newsgroup which isn't
overrun by egomaniacs and trolls :)

@linards - I don't have a serial card so the cassette port is the only
option for me until my ebay purchase arrives in a few weeks. I'm sure
game server will come into its own at that point. I haven't got
integer basic but thanks anyway for the startrek offer.

@schmidtd - you're right - a quick look at the source to adtpro should
yield what I need to make a program -> kansas converter.

Except that it's *not* Kansas format.  Woz chose a simple 1kHz-2kHz
encoding that achieves an average 1500 bits/sec.  Only the zero-crossing
times are used to discriminate the frequencies.  Two half-cycles of
each frequency per bit, polarity unimportant.

Take a look at the monitor routines that read and write cassettes and
you'll see what you need to do--including the short length-containing
record that precedes the data.

@bryan - I've implemented a number of raw data <-> coded audio
programs in c++ for various retro systems. So if I can be of any help
I'd be delighted. They're not that hard as long as you've got good
documentation about the format.

Bingo--and the monitor code is the place to understand the cassette
format.

-michael

NadaPong: Network game demo for Apple II computers!
Home page:  http://members.aol.com/MJMahon/

"The wastebasket is our most important design
tool--and it's seriously underused."