Path: utzoo!attcan!uunet!lll-winken!lll-tis!ames!mailrus!nrl-cmf!cmcl2!rutgers!njin!princeton!udel!udccvax1!gdtltr From: gdtltr@vax1.acs.udel.EDU (Gary D Duzan) Newsgroups: comp.sys.atari.8bit Subject: Re: Need a cassette tape drive. Message-ID: <2170@udccvax1.acs.udel.EDU> Date: 20 Oct 88 02:49:01 GMT References: <736@wsccs.UUCP> <4408@bsu-cs.UUCP> Reply-To: gdtltr@vax1.acs.udel.EDU (Gary D Duzan) Organization: University of Delaware Lines: 55 In article <4408@bsu-cs.UUCP> cfchiesa@bsu-cs.UUCP (Christopher Chiesa) writes: >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. > >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.) > Agreed about drives. I think tape recorders hate me (I, naturally enough, reciprocate). There are a couple problems with the XF551, but nothing that can't be overcome with a little hacking. >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.) > I think you will find it more complicated than you think. Remember that all I/O devices attached to the SIO port MUST BE INTELLIGENT!!! I believe the 1050 drive has a microprocessor almost as powerful as the 6502 (not a great statement, but it is better than nothing). An SIO call sends data to the processor on the device and the device responds with the proper data, not just some sounds. There is a pin on the SIO to allow an audio signal to pass though the computer and out through your monitor speaker and a motor on/off pin, so you could probably get it to play, but reading data off it is out of the question without a processor chip. >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. > If necessary, you could probably tap lines in an existing cable. I know a couple people who built a voice synthesizer called Cheap Talk (it fits in a cassette tape box). The synthesizer was controlled through one of the joystick ports, but instead of hooking the output to an external speaker, he stole the audio in line from an existing SIO cable and send the output there, routing the sound through his monitor. If you want to look at the pinouts of the SIO interface, they are in Mapping the Atari XL/XE version p.198. Gary Duzan Time Lord Third Regeneration Atari Enthusiast Extreme