ckoba Posted February 10, 2016 Share Posted February 10, 2016 Guys, I remember writing this! Stumbled upon this forum by accident. What do you want to know... When I first started experimenting with the CRU inputs to read "the beeps from the cassette tape", I figured the format for basicode out at some point. It's pretty straightforward, with two frequencies, startbit, stopbit etc. I then applied the very same knowledge to create AFSK telex decoder, ZX-Spectrum loader, and turbo loader for the 4A. The latter was just the basicode format with less delay. Oh, how very nice to have the original author available for consultation Is the TI fastloader compliant with the protocol as described in http://www.brutaldeluxe.fr/projects/cassettes/bbc/k7_bbc_thechipshop_manual_ocr.pdf ? The loader portion expects to run from BASIC and controls the tape motor to start playback, yes? What is the timeout duration until it gives up waiting for data, or will it wait forever? 1 Quote Link to comment Share on other sites More sharing options...
TonB Posted February 10, 2016 Share Posted February 10, 2016 What I'm looking for is the frequency for 1 and 0. I can work it out from there. Ultimately this will be folded into my bin->tape .wav generator, I think, but Ron just wants to see it working in any way possible The way I implemented the loader back in the days, is to sample the frequencies during the lead-in tone of the playback. Then you can calibrate the speed of the CPU against the speed of the tape. With this mechanism you can speed up the tape if you want, and if your CPU can keep up, load even faster. You can then implement a loader without any magic constants, since they're all calculated on the fly. 1 Quote Link to comment Share on other sites More sharing options...
+mizapf Posted February 10, 2016 Share Posted February 10, 2016 Tonny, maybe you saw my post in this thread - I have a problem with the cassette routine in MESS. It does not start the cassette motor. The console cassette driver works without problems. In MESS you can see that the motor is active by a small pop-up window that shows the increasing cassette drive counter. Quote Link to comment Share on other sites More sharing options...
TonB Posted February 10, 2016 Share Posted February 10, 2016 Tonny, maybe you saw my post in this thread - I have a problem with the cassette routine in MESS. It does not start the cassette motor. The console cassette driver works without problems. In MESS you can see that the motor is active by a small pop-up window that shows the increasing cassette drive counter. The way I remember it the cassette on/off switch is just another CRU register. Why not disconnect the motor control and start/stop the tape manually when the routine starts listening? I remember I had a cassette player that even didn't allow motor control... The turboloader I wrote was derived from the basicode protocol. I think I increased the frequencies to the max that was achievable with somewhat reliable readback. I may have thrown out one of the two stop bits for an extra couple of percent... not sure. Quote Link to comment Share on other sites More sharing options...
+mizapf Posted February 10, 2016 Share Posted February 10, 2016 The problem is that the emulation assumes that the cassette motor is explicitly turned on and off by the CRU bit. If I wanted to get your loader running in MESS I would have to include a special switch just for this purpose. It would probably be easier to have a version of the loader that contains the missing SBO. Quote Link to comment Share on other sites More sharing options...
ti99iuc Posted May 23, 2018 Share Posted May 23, 2018 Hello Globeron, all files linked in the first post are unavailable, could you put them online again please ?thanks Ciro 1 Quote Link to comment Share on other sites More sharing options...
jrhodes Posted May 24, 2018 Share Posted May 24, 2018 Hello Globeron, all files linked in the first post are unavailable, could you put them online again please ? thanks Ciro I was also curious about that mp4 file at the bottom of page 1, could that be put back online also? Quote Link to comment Share on other sites More sharing options...
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