Forum Rule: Always post complete source code & details to reproduce any issue!
Results 1 to 10 of 10

Thread: Teensy 3.6 "PassThroughStereo" issue

  1. #1
    Junior Member
    Join Date
    Oct 2016
    Posts
    13

    Teensy 3.6 "PassThroughStereo" issue

    Hey everyone,

    Just picked up the Teensy 3.6 today, and I've been busy messing around with all the example sketches yet again for some fun, and to make sure everything works as I expected.

    All of the sketches so far worked identical - with one exception: "PassThroughStereo" which doesn't seem to get any input at all when compiled for the Teensy 3.6. I noticed that if I drop the clock speed down to 96mhz or lower, it runs perfectly. Any insight? I'm quite new to this, but given that all the other sketches work perfectly, I thought I'd reach out here for some advice.

    I'm using the standard "PassThroughStereo" sketch included in the Teensy library, a Teensy 3.6, and the Teensy Audio Adapter. I'm compiling the sketch using Arduino on Mac.

    Thanks for any help!

  2. #2
    Senior Member+ defragster's Avatar
    Join Date
    Feb 2015
    Posts
    10,619
    Seems like this may be related to this discussion on this post and those just before it :: Excellent-results-with-Floating-Point-FFT-IFFT-Processing-and-Teensy-3-6?

  3. #3
    Junior Member
    Join Date
    Oct 2016
    Posts
    13
    Thank you,

    That does indeed seem to be the same issue. I searched the forums before posting, but clearly not throughly enough. Thank you very much for pointing me in the right direction!

  4. #4
    Senior Member
    Join Date
    Nov 2012
    Posts
    1,228
    This is a continuation of some discussion on the topic of problems with audio here.

    With the new fix and using the WavFilePlayer example I get somewhat different symptoms from my passthru mic example but overall the results are the same.
    On a new T3.6
    Up to and including 192MHz the WAV files play with no problems.
    @216MHz it sounds like the 44.1kHz clock (or its source) is wandering all over the place. The playback speed varies widely.
    @240MHz it appears to be working for a while but then it just stops playing altogether right in the middle of a track.

    With my pasthru mic example there is constant clicking at 216MHz. At 240MHz it is nowhere near as frequent but it's still there and also the audio output sometimes just stops altogether.


    In 997 I noted the measurements of the audio clocks I made with a multimeter and then in 999 I posted a "fix" which stabilized the clock at 240MHz but at double its correct rate. Don't know if this was even the correct thing to do but might be relevant.

    Pete

  5. #5
    Senior Member+ Frank B's Avatar
    Join Date
    Apr 2014
    Location
    Germany NRW
    Posts
    6,223
    @el_supremo, it's not only with wave-files - it's independent of the source. I reported that issue several times ("Funny Pitch") .)
    But it's with overclocking only - so not a real problem.
    It sounds like it rries to sync with a non-existing source, or like pressing a finger on a vinyl record during playing.

    It's for I2s with audioshield only - I did not notice the problem with PT8211, which is I2s, too ?
    They are almost the same. PT8211 uses an other I2S-format and does not enable I2S Input..
    Last edited by Frank B; 10-23-2016 at 10:26 PM.

  6. #6
    Senior Member
    Join Date
    Nov 2012
    Posts
    1,228
    Frank: Paul asked for "something that runs stand-alone from synthesis or known WAV files is preferable for reproducibility". I've already noted, as you have, that the source doesn't appear to be the problem.

    Pete

  7. #7
    Senior Member+ Frank B's Avatar
    Join Date
    Apr 2014
    Location
    Germany NRW
    Posts
    6,223
    Yes, the PlaySynthMusic example.
    Last edited by Frank B; 10-23-2016 at 10:41 PM.

  8. #8
    Senior Member+ defragster's Avatar
    Join Date
    Feb 2015
    Posts
    10,619
    That PlaySynth is the one I tried and found/posted to work on my beta T_3.6 and PJRC Audio Shield.
    Excellent-results-with-Floating-Point-FFT-IFFT-Processing-and-Teensy-3-6?
    I'll try again when TD_1.3.b2 releases in case a local system change was behind that. I haven't soldered any of my KS T_3.6 yet.

    Another simple sample would be good

  9. #9
    Senior Member+ Frank B's Avatar
    Join Date
    Apr 2014
    Location
    Germany NRW
    Posts
    6,223
    hm. but in the beta-test you reported that pitch-problems, too ? (do i remember correctly ?)
    was it with "play from sd" ?

    i have these pitch-problems regardless of the source..

  10. #10
    Senior Member+ defragster's Avatar
    Join Date
    Feb 2015
    Posts
    10,619
    Quote Originally Posted by Frank B View Post
    hm. but in the beta-test you reported that pitch-problems, too ? (do i remember correctly ?)
    was it with "play from sd" ?

    i have these pitch-problems regardless of the source..
    Me? - IIRC - I had an issue with Talkie very early on before the frequency stuff you cleared up worked (and located the DAC pin). I haven't done a lot of other Audio stuff that would have shown issues.

    I did run the one posted sample with {not that one} mic in - that was the day I got my beta T-3.5 - not sure I ran on T_3.6 - but that mic sample worked.

    The Vocoder sample was OVERSIZE and should work now - not sure that was any other issue.

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts
  •