khayo@MATH.UCLA.EDU (07/30/87)
Hello ATARI-land; I'm new to this group, and I don't even have
an Atari (!) [please, no flames], so my request may be very
naive, silly or worse...
A friend of mine, who is completely shut off from the marvels
of information age due to the part of our world he lives in, just
got an Atari 800XL. My conjecture is that he would like to get
some freeware/shareware for it - he was tactful enough not to ask
me explicitly. Since I have access to all kinds of BBS, networks
etc, I should be able to get a lot of nice stuff for him.
So where's the problem, you may ask? Elementary, Watson - I
am a Macintosh type, so I would be downloading all these goodies
into my Mac+, and there is an obvious question of how to
transfer a Mac text file to an 800XL medium. Now my main question:
what is the format in which the 800XL likes data to be stored on
tape? If it is the TI/99A-like FSK modulation, I could probably
write a trivial program that would force my Mac to simulate an
Atari output via a sound synthesiser & the speaker jack - I'd
then record this & send a cassette to my buddy. Does it hold
water? If it does, I'd be eternally grateful for any info/pointers
on the subject (as far as tape format goes, I'd obviously need
both the hardware [modulation method] & software [file format] side
of the story.
Thank you very much in advance. This thing may not be of general
interest, so please E-mail me at khayo@MATH.UCLA.EDU (regardless
of what the header may say - our news software screws that up on
occasion).
Eric Behrpkopp@houligan.UUCP (Paul Kopp) (08/02/87)
in article <7477@shemp.UCLA.EDU>, khayo@MATH.UCLA.EDU says: > > > (stuff deleted) > Now my main question: > what is the format in which the 800XL likes data to be stored on > tape? If it is the TI/99A-like FSK modulation, I could probably > write a trivial program that would force my Mac to simulate an > Atari output via a sound synthesiser & the speaker jack - I'd > then record this & send a cassette to my buddy. WOW...this sounds like _ALLOT_ of work. Before I started writing programs, I would try to convince my friend to buy a $35-$40 XM-301 modem for his Atari. You could then download binarys/text to your Mac and transfer them over to him. Anyway, to answer your question: (this stuff comes from _De_Re_Atari_) Ataris write fixed-length blocks at 600 baud (to tape). Two frequencies are used: 5327 hz. for a mark (or 1) and 3995 hz. for a space (or 0). A byte is defined by: 1 start bit (space) 0-7 data bits (marks and spaces) 1 stop bit (mark) Records should be written to the tape in the form of: 01010101 1st marker 01010101 2nd marker (markers are for speed measurement) control byte 128 data bytes checksum The control byte is defined as: $FC indicates the record is a full 128 byte data record. $FA indicates the record is a partial record (less than 128 bytes). $FE indicates the record is an EOF. NEED I SAY MORE?
khayo@CS.UCLA.EDU (08/03/87)
Thanks a lot to all who responded to my question. I'm all set,
having received lots of detailed data from at least two sources.
I'll try to play with it, realizing very well that it would
be much easier to simply get a disk drive for my friend (as for
the option of sending stuff via modem: if you had anything to
do at all with the Polish telephone system, you wouldn't say a
single bad word about MCI & the like - so that's out. I mentioned
in my first posting that the source of all problems is my friend's
geographic location.)
Thanks again -
Eric
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I'm sick & tired of editing my incorrect address in the header.
The *correct* one is khayo@MATH.UCLA.EDU; I have no connection
with the CS Department, except that we breathe the same smog.