swillden@wsccs.UUCP (Shawn Willden) (10/14/88)
I need an interface for a cassette tape for an atari 800XL. I don't know if I need just an interface or an atari tape recorder too. I might be interested in getting a disk drive instead, if the price is low enough. I can probably build my own interface to a tape drive if it is not too incredibly complicated and if someone can tell me where to get a 13-pin male connector. Could someone please point me in the right direction, or at least tell me what I need? If you're considering junking your old atari or have an extra interface lying around somewhere, I would be willing to pay for it. e-mail your responses to me. swillden@wsccs
cfchiesa@bsu-cs.UUCP (Christopher Chiesa) (10/20/88)
In article <736@wsccs.UUCP>, swillden@wsccs.UUCP (Shawn Willden) writes: > I need an interface for a cassette tape for an atari 800XL. I don't > know if I need just an interface or an atari tape recorder too. I might > be interested in getting a disk drive instead, if the price is low > enough. I can probably build my own interface to a tape drive if it > is not too incredibly complicated and if someone can tell me where to > get a 13-pin male connector. 1) You don't need an 'interface' if you obtain an Atari cassette drive - they are made to plug right into the SIO port, although they have only ONE SIO connector and therefore "terminate" any daisy chain. (This implies that you can't have the cassette unit and any OTHER terminating peripheral (the SX212 modem in SIO-direct mode, for example) connected at the same time.) There are two units in existence that I know of, the 410 and (someone cor- rect me if I'm wrong) the 1010. The 410 is of the 400/800 generation, and the 1010 is of the XL generation, but EITHER should work with ANY 8-bit Atari. I personally have a 410 that I rarely use, but have just recently thought of an interesting use for cassette storage, so am loath to sell... sorry. 2) Disk drives are infinitely better: faster, random-access, more space. I HAVE heard, however, from a friend who got the new XM551 drive and does NOT like it... (Ooh, I can feel the flames already... ask 'aegnor@bsu-cs' about Mike W's experience; 'aegnor' is the one who was telling ME.) 3) I don't imagine the interface to a standard tape recorder should be too complicated; data is stored and retreived as audio tones on, I believe, the LEFT channel of a standard stereo recording, with capability to play right-channel audio through the TV/monitor speaker! You should be able to simply connect the audio inputs, outputs, and ground, to the appropriate SIO pins, as well as using some kind of control circuit (I do NOT recommend direct connection here) to turn the cassette player's MOTOR on and off in response to the appropriate SIO signals. (On the other hand, you could probably get away with leaving it ALWAYS on, in some if not all cases. There ARE cases where the computer NEEDS to start and stop the tape, however.) 4) Alas, I don't know where to get an SIO plug, but there must be SOMEPLACE since there is a continuing flow of SIO cables etc. Scavenge a cable if you have to. Probably the easiest way of obtaining one, when you get right down to it. Hope this is helpful; good luck! If you DO hack together an interface to a standard cassette recorder, let me know; I have a reel-to-reel I'd like to try using... Chris Chiesa almost gone from Ball State University -- UUCP: <backbones>!{iuvax,pur-ee,uunet}!bsu-cs!cfchiesa cfchiesa@bsu-cs.UUCP
charles@c3sw.uucp (Charles Green) (11/02/88)
In article <4408@bsu-cs.UUCP> cfchiesa@bsu-cs.UUCP (Christopher Chiesa) writes: >1) You don't need an 'interface' if you obtain an Atari cassette drive - they > are made to plug right into the SIO port, although they have only ONE SIO > connector and therefore "terminate" any daisy chain. (This implies that The Atari 1010 program recorder (I have one) has two SIO connectors. > I HAVE heard, however, from a friend who got the new XM551 drive and does NOT > like it... I have the Atari 1050 disk drive, and DO like it, although I wish it did "true" double density, with twice the data storage of single-density, rather than half again. And imagine what 512-byte sector support could do for program interchange: "Sure, I can read that PC-DOS diskette!" (Happy Computers Inc, are you listening?). > about Mike W's experience; 'aegnor' is the one who was telling ME.) > complicated; data is stored and retreived as audio tones on, I believe, > the LEFT channel of a standard stereo recording, with capability to play > right-channel audio through the TV/monitor speaker! You should be able > to simply connect the audio inputs, outputs, and ground, to the appropriate > SIO pins, as well as using some kind of control circuit (I do NOT recommend As already pointed out, the Atari uses the Pokey two-tone mode to output FSK on the serial output pin. (This FSK is, alas, apparently not phase-coherent, which may be why we are limited to 600 bauds.) Thus, you can *record* Atari tapes, with no further electronics, on a standard cassette deck. To read them back, however, you must present the decoded data to the serial input pin. That requires an FSK demodulator, the only "magic" in the Atari program recorder. Before I bought my Atari 1010, I bought an Exar XR2211 FSK Demodulator chip, and got excellent results writing and reading tapes. In fact, the 1010 gave much *worse* performance than my simple one-chip solution! One of these days, I'll do some serious experimenting with some custom tape I/O software and the XR2206 (phase-coherent) FSK modulator. If a Bell 103 can do 300 baud in 1.5kHz bandwidth, 12kHz on a tape deck would give 4800bps and using all four tracks in a stereo deck will yield 5 Megabytes on a C-90. -- Charles Green charles@c3pe.UUCP {decuac,cucstud}!c3pe!charles
slackey@bbn.com (Stan Lackey) (11/02/88)
>In article <4408@bsu-cs.UUCP> cfchiesa@bsu-cs.UUCP (Christopher Chiesa) writes: >One of these days, I'll do some serious experimenting with some custom tape >I/O software and the XR2206 (phase-coherent) FSK modulator. If a Bell 103 In my pre-atari, pre-sinclair days, I was fooling around with a home-built 6800-based system. I built a simple mod-demod with a 555 (voltage controlled osc) and 556(?) phase locked loop. I connected a UART to the 6800, and connected the serial I/O from the UART into my widget. I used freq's like 3000Hz for a 1 and 3300 for a 0 or so. It worked totally reliably at 1200 baud! I guess I should have tried it at higher baud rates... I had fun anyway. -Stan
cfchiesa@bsu-cs.UUCP (Christopher Chiesa) (11/03/88)
In article <31750@bbn.COM>, slackey@bbn.com (Stan Lackey) writes: > >In article <4408@bsu-cs.UUCP> cfchiesa@bsu-cs.UUCP (Christopher Chiesa) writes: > >One of these days, I'll do some serious experimenting with some custom tape > >I/O software and the XR2206 (phase-coherent) FSK modulator. If a Bell 103 > No, I DIDN'T write that. That was written by the person who quoted part of my earlier posting. Chris -- UUCP: <backbones>!{iuvax,pur-ee,uunet}!bsu-cs!cfchiesa cfchiesa@bsu-cs.UUCP