Hi Vasiele and others. I was born before the last world war and I suspect most of you after it. I hope it stays that way!! Great, I can study today again. Thank you.
Op vrijdag 25 februari 2022 om 06:58:52 UTC+1 schreef vasile: > Kiste, not only the ZX81 but Sinclair Spectrum and most of it's clones did > the same. > The biggest problem was the tape speed variation (among the volume > variation which was corrected in romanian clones -and we had more than any, > I recall 5 different types). > > Hans, on the actual PIC18 series on which JAL works ( presuming you will > do with JAL) you might have some sampling speed issues. You need at least > 7.5us for an ADC sample and according to Nyquist theorem you need not 2x ( > which is pure theoretical) but at least 4x faster sampling than maximum > frequency you are recording. > After your AD is sampled, the PWM is not an issue, but you might > experience a small delay between real recorded speech and the PWM filtered > one. > If you plan to add voice for your puppet, then limiting to 4KHz may be a > good choice. > > best wishes, > hopefully not WW III, but in pace for playing nice... > > On Thu, Feb 24, 2022 at 10:38 PM 'Oliver Seitz' via jallib < > [email protected]> wrote: > >> Hi Rob, >> >> connecting two PICs is not like an audio recording. Better connect the >> pic to your soundcard to record and then playback, that way you'll get >> something similar to a tape recorder. >> >> The difficulties when using audio equipment are (at least): >> >> - only alternating current is transmitted >> - the volume is never exactly the same >> - the frequency range is limited to like 100Hz-10kHz >> - the line level voltage is less than 1V >> >> Reading should be possible by most PICs which have comparators. Only a >> resistor is needed, then you can detect zero crossings. >> >> The Sinclair ZX81 used audio equipment as storage. A burst of three >> oscillations coded a zero, five coded a one. The output was low-pass >> filtered. You usually had to try loading a program several times, slightly >> adjusting the volume, until you got lucky. >> >> Greets, >> Kiste >> >> Am Donnerstag, 24. Februar 2022, 19:56:01 MEZ hat Rob CJ < >> [email protected]> Folgendes geschrieben: >> >> >> Hi Hans, >> >> If I understand you right the only thing you want to do is to record a >> signal or a sequence of signals on a casette player that can be used to >> trigger something when the recording is played back right? >> >> If my initial suggestion would work - which may work since I have the >> idea that my Apple II did more ore less the same thing - I could give it a >> try to do a proof of concept. >> >> I may have a the problem that I do not have a casette recorder but I >> could fake it by just connecting two PICs to see if that works. The final >> test could then be done by you. >> >> Which PIC type are you using? >> >> Kind regards, >> >> Rob >> >> >> >> ------------------------------ >> *Van:* [email protected] <[email protected]> namens hans < >> [email protected]> >> *Verzonden:* donderdag 24 februari 2022 17:07 >> *Aan:* jallib <[email protected]> >> *Onderwerp:* Re: [jallib] PWM serial audio transmission >> >> Another piece of text: >> So far I've done everything with MIDI. I used one midi channel for the >> actions with a general command type. Then 2 data, one for the device nr >> (16) and one for the command. (0-128) >> This has worked well for years, but it does require a complete MIDI sound >> package. >> >> Op donderdag 24 februari 2022 om 16:55:46 UTC+1 schreef hans: >> >> Hey , >> I have tried a circuit with an MT8880 but the ICI has failed. I did hear >> the 16 tones, but when I wanted to receive them, the chip gave up the ghost. >> In theory I understand your suggestions well, but developing something >> like this is not easy for me. I'm just a LEGO builder. >> regards >> Hans >> >> Op woensdag 23 februari 2022 om 19:30:37 UTC+1 schreef [email protected] >> : >> >> Hi Hans, Kiste, >> >> You can still by DTMF decoders and I assume also DTMF encoders. Just look >> at for example Aliexpress and type DTMF. >> >> But another suggestion. Many, many years ago I had built an Apple II and >> I used cassette tapes to store and load games which was using tones >> generated by the Apple II itself using two tones, one for high, one for low >> and one as a lead-in tone (not sure in the lead-in tone was another tone) >> to synchronze the start of the recorded program. You would not need this >> lead-in tone in your case >> >> So I think it may not be that complex: >> -) For recording on casette, generate this dual tone by the PIC via PWM >> or maybe it is also sufficient to generate one tone in case of a 1 and no >> tone in case of a 0 but I think this will be less reliable. >> -) For playback, measure the length of the recorded PWM tone. If is is >> within a certain range you accept it as a one and in case of two tones the >> lower tone could be zero and the higher tone is one. >> >> As long as the tone frequency is not too high, I think this could work. >> >> A more advanced solution would be to use a phase locked loop (PLL) but I >> am not sure if it will work. The PLL locks to the input signal so the >> voltage that controls the oscillator goes up and down to follow (lock on >> to) the input signal and this oscillator voltage signal could then be used >> by a comparator of the PIC to detect a high or low tone. You can also use >> the oscillator of the IC to generate the two tones by controlling the >> oscillator voltage by the PIC. A typical IC for that is the HEF4046. I have >> used this IC many many years ago too. This solution may be bit over the top >> since you only want a kind of trigger signal >> >> But maybe the first solution is more doable. Just give it a try. >> >> Kind regards, >> >> Rob >> >> ------------------------------ >> *Van:* 'Oliver Seitz' via jallib <[email protected]> >> *Verzonden:* woensdag 23 februari 2022 09:58 >> *Aan:* [email protected] <[email protected]> >> *Onderwerp:* Re: [jallib] PWM serial audio transmission >> >> Hi Hans, >> >> 20 years ago I would have suggested using DTMF, but the decoder chips are >> rare these days... >> >> PIC controllers include various peripherals which can be used to encode >> and decode DC-free signals (which, apart from the frequency below, say, >> 10kHz, is the requirement to be recorded as audio). On/off keying or >> frequency shift keying are the easiest, I think. Which chips are you going >> to use? >> >> Greets, >> Kiste >> >> Am Mittwoch, 23. Februar 2022, 09:15:43 MEZ hat hans < >> [email protected]> Folgendes geschrieben: >> >> >> Hello everyone, >> I have been trying for a long time to place a serial signal on one track >> of an audio recording which I can read afterwards. To make all kinds of >> things happen at the same time as the audio is played. I have now tried to >> do this with the old modem system ( TCM3105) but it failed hopelessly. I >> read that there are also systems to do this using PWM. Does anyone have an >> idea? >> regards >> Hans >> >> -- >> You received this message because you are subscribed to the Google Groups >> "jallib" group. >> To unsubscribe from this group and stop receiving emails from it, send an >> email to [email protected]. >> To view this discussion on the web visit >> https://groups.google.com/d/msgid/jallib/773ca37b-9bed-4349-a8eb-32a5d8973df6n%40googlegroups.com >> >> <https://groups.google.com/d/msgid/jallib/773ca37b-9bed-4349-a8eb-32a5d8973df6n%40googlegroups.com?utm_medium=email&utm_source=footer> >> . >> >> -- >> You received this message because you are subscribed to the Google Groups >> "jallib" group. >> To unsubscribe from this group and stop receiving emails from it, send an >> email to [email protected]. >> To view this discussion on the web visit >> https://groups.google.com/d/msgid/jallib/201142693.752814.1645606718467%40mail.yahoo.com >> >> <https://groups.google.com/d/msgid/jallib/201142693.752814.1645606718467%40mail.yahoo.com?utm_medium=email&utm_source=footer> >> . >> >> -- >> You received this message because you are subscribed to the Google Groups >> "jallib" group. >> To unsubscribe from this group and stop receiving emails from it, send an >> email to [email protected]. >> To view this discussion on the web visit >> https://groups.google.com/d/msgid/jallib/d4803c41-505a-4297-81d5-7be0ef06b112n%40googlegroups.com >> >> <https://groups.google.com/d/msgid/jallib/d4803c41-505a-4297-81d5-7be0ef06b112n%40googlegroups.com?utm_medium=email&utm_source=footer> >> . >> >> -- >> You received this message because you are subscribed to the Google Groups >> "jallib" group. >> To unsubscribe from this group and stop receiving emails from it, send an >> email to [email protected]. >> To view this discussion on the web visit >> https://groups.google.com/d/msgid/jallib/DB6P195MB018301D93CBE73C8A9C74FF0E63D9%40DB6P195MB0183.EURP195.PROD.OUTLOOK.COM >> >> <https://groups.google.com/d/msgid/jallib/DB6P195MB018301D93CBE73C8A9C74FF0E63D9%40DB6P195MB0183.EURP195.PROD.OUTLOOK.COM?utm_medium=email&utm_source=footer> >> . >> >> -- >> You received this message because you are subscribed to the Google Groups >> "jallib" group. >> To unsubscribe from this group and stop receiving emails from it, send an >> email to [email protected]. >> > To view this discussion on the web visit >> https://groups.google.com/d/msgid/jallib/1712343432.941652.1645735109957%40mail.yahoo.com >> >> <https://groups.google.com/d/msgid/jallib/1712343432.941652.1645735109957%40mail.yahoo.com?utm_medium=email&utm_source=footer> >> . >> > -- You received this message because you are subscribed to the Google Groups "jallib" group. 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