Forum Rule: Always post complete source code & details to reproduce any issue!

Search:

Type: Posts; User: jonr

Page 1 of 10 1 2 3 4

Search: Search took 0.01 seconds.

  1. Replies
    2
    Views
    60

    Following the manufacturer recommendation sounds...

    Following the manufacturer recommendation sounds reasonable. Is there something that prevents the battery from being discharged to an unsafe voltage?
  2. Replies
    52
    Views
    2,969

    A differential ADC on the Teensy 3.6 (Pins A10...

    A differential ADC on the Teensy 3.6 (Pins A10 and A11) should work well for this application.
  3. Don't worry about the ":02 0000 02" lines, they...

    Don't worry about the ":02 0000 02" lines, they aren't code values. But for now, do manually combine any ":04 XXXX 00" lines.
  4. Replies
    26
    Views
    339

    No doubt there are some users who are able to...

    No doubt there are some users who are able to "insert the SD card I mailed you" and not "install this software on your PC and then ....". You can start with "Flasher4" if you want to develop...
  5. Replies
    10
    Views
    268

    If you just want an easy low noise teensy output...

    If you just want an easy low noise teensy output solution, run toslink to an off-the-shelf DAC/amp.
  6. Replies
    13
    Views
    283

    i2sflew: I highly recommend that you get used to...

    i2sflew: I highly recommend that you get used to typing your circuits into LTSpice. You can even add noise to the power supply or input. Not perfect, but you will learn a lot.
  7. Replies
    10
    Views
    268

    How does it sound when you run from batteries?

    How does it sound when you run from batteries?
  8. Replies
    13
    Views
    283

    "the AD8656 can drive capacitive loads up to 500...

    "the AD8656 can drive capacitive loads up to 500 pF ..."

    So if you are planning to us it there, think twice about that 33uF.
  9. > a DSB is mandatory at the end of interrupt-code...

    > a DSB is mandatory at the end of interrupt-code

    I believe it should also be used when disabling interrupts from non-interrupt code.

    > SCB_AIRCR = 0x05FA0004;

    Of course such things...
  10. Replies
    13
    Views
    283

    You might be better off just ordering this: ...

    You might be better off just ordering this:

    https://www.pjrc.com/store/audio_ground_isolator.html
  11. It would be really nice if the flasher code could...

    It would be really nice if the flasher code could directly accept any .hex lines it is likely to receive.
  12. Replies
    13
    Views
    207

    I would study the example below. Look closely at...

    I would study the example below. Look closely at how/where "client" is set.

    https://gist.github.com/atomsfat/1813823
  13. Replies
    92
    Views
    12,023

    > A simple hardware diagnostic using patterns of...

    > A simple hardware diagnostic using patterns of red LED blinks is also planned

    Nice! - black boxes are hard to debug. Would be very helpful to distinguish between "loader can't talk to MCU",...
  14. That is my concern. Some protocols are likely to...

    That is my concern. Some protocols are likely to lose exactly an entire line. This could get flashed and the error might not be immediately obvious.
  15. > you need to type in ":flash XXXX", where XXXX...

    > you need to type in ":flash XXXX", where XXXX is the number of lines reported by the program

    I recommend that you don't do this. Type in ":flash XXXX", where XXXX is the number of lines you...
  16. Replies
    22
    Views
    348

    For speaker analysis and correction, this is...

    For speaker analysis and correction, this is great.

    https://www.roomeqwizard.com/

    If you want to do convolution based correction, then just use the impulse response from REW and also use...
  17. Replies
    22
    Views
    348

    Yes, specifically "fast, partitioned convolution".

    Yes, specifically "fast, partitioned convolution".
  18. Replies
    22
    Views
    348

    While it's only necessary for high resolution at...

    While it's only necessary for high resolution at low frequencies, I am able to run 12288 taps, stereo.
  19. Replies
    18
    Views
    401

    OK, I checked and some notes: T4 with a small...

    OK, I checked and some notes:

    T4 with a small heat sink attached
    It runs about 45C (far far different than the graph)
    Slowing from 600 to 528 is only a couple of degrees cooler
    wfi makes no...
  20. Replies
    18
    Views
    401

    In many cases, one could include this in their...

    In many cases, one could include this in their idle loop, which I understand reduces power/heat more than slowing down to 450 mhz.

    asm volatile("wfi");
  21. Replies
    18
    Views
    401

    My guess is that at 450 mhz, it will last a very...

    My guess is that at 450 mhz, it will last a very long time. And most applications won't notice the slower speed.
  22. Replies
    628
    Views
    57,275

    There was some discussion of strlcpy(). IMO,...

    There was some discussion of strlcpy(). IMO, don't just use it, use it and check the return value. Ie:



    if (strlcpy(dest, src, sizeof(dest)) > sizeof(dest))
    handle_error();
  23. Replies
    18
    Views
    401

    3 years life at 600 mhz - that could be a problem.

    3 years life at 600 mhz - that could be a problem.
  24. Sure, you could pack four 10 bit samples into...

    Sure, you could pack four 10 bit samples into every five bytes. But consider other approaches - like a teensy 4.1 or a larger sd card.
  25. Replies
    58
    Views
    1,747

    My experience is that paste is better, even when...

    My experience is that paste is better, even when you don't have a stencil. But I save time and frustration - unless JLCPCB puts most of the parts on, I always order a stencil. More advice - use a...
  26. Replies
    22
    Views
    348

    I agree with tomas. Is there a tool for...

    I agree with tomas. Is there a tool for predicting how many bits you need for how much distortion?
  27. Replies
    14
    Views
    232

    Consider either headphones (low bass with low...

    Consider either headphones (low bass with low power) or a subwoofer (which will need size and power).
  28. Replies
    22
    Views
    2,199

    For about $15, you can buy an external TOSLINK...

    For about $15, you can buy an external TOSLINK DAC box. Not the lowest cost option, but will probably outperform the PT8211.
  29. Replies
    95
    Views
    23,799

    Yes, it works on both 4.0 and 4.1.

    Yes, it works on both 4.0 and 4.1.
  30. Replies
    95
    Views
    23,799

    See here for a newer, better teensy 3.x version:...

    See here for a newer, better teensy 3.x version:

    https://forum.pjrc.com/threads/43165-Over-the-Air-firmware-updates-changes-for-flashing-Teensy-3-5-amp-3-6
  31. Nice work Joe.

    Nice work Joe.
  32. Replies
    16
    Views
    446

    I use the audio library with USB input and SPDIF...

    I use the audio library with USB input and SPDIF optical output. I have no noise issues.

    You haven't explained what you need to do, but stay digital as much as possible and if you have to do a...
  33. Replies
    58
    Views
    1,747

    Nice! Can you make a iMXRT1062 version too? ...

    Nice!

    Can you make a iMXRT1062 version too? :-)
  34. Replies
    11
    Views
    232

    For less noise, you should be doing a...

    For less noise, you should be doing a differential read on two analog inputs.
  35. What options are available on a teensy to do...

    What options are available on a teensy to do bounds checking? Ie, what's the easiest way to find the above error?
  36. Replies
    106
    Views
    4,091

    IMO, the memory allocation details should be...

    IMO, the memory allocation details should be abstracted away for the typical use case. Ie, a single mallocX() call where you optionally pass it a hint as to the speed desired (or other...
  37. Replies
    6
    Views
    308

    I'd use the existing routine for writing blocks. ...

    I'd use the existing routine for writing blocks. Specifically:

    void eeprom_write_block(const void *buf, void *addr, uint32_t len)
  38. Replies
    6
    Views
    151

    I'm curious, is there any reason that the library...

    I'm curious, is there any reason that the library shouldn't have an empty constructor and do the initialization in begin()? In any case, just crashing is poor design.
  39. Replies
    695
    Views
    442,463

    My understanding is that if you omit the stop,...

    My understanding is that if you omit the stop, then the bus isn't released and, with your slave chip/application, the following start isn't needed/tolerated.
    But the libraries don't provide a way...
  40. Replies
    695
    Views
    442,463

    Good that you found something that works. As I...

    Good that you found something that works. As I see it, your application could use less buffer space if it had something like this for all but the first and last portions:
    ...
  41. Replies
    695
    Views
    442,463

    You should post your actual code. I don't...

    You should post your actual code. I don't know much about it, but possibly use wait_idle() between partial writes.
  42. Replies
    695
    Views
    442,463

    Can you do many smaller writes? What is the...

    Can you do many smaller writes? What is the target chip and software running on it?
  43. There is a nice spreadsheet coefficient...

    There is a nice spreadsheet coefficient calculator/visualizer here:

    https://www.minidsp.com/applications/advanced-tools/advanced-biquad-programming

    +1 on using the teensy code (see...
  44. Thread: Audio filter

    by jonr
    Replies
    10
    Views
    468

    > The geometric mean gives 965Hz, i.e. 35Hz...

    > The geometric mean gives 965Hz, i.e. 35Hz bellow the 1000Hz

    I get:

    sqrt(1390*720) = 1000.4 Hz
  45. Replies
    92
    Views
    12,023

    If you really need a custom iMXRT1062 design now,...

    If you really need a custom iMXRT1062 design now, then I'd design it for both a MKL02 and a jtag connector.
  46. Thread: Audio filter

    by jonr
    Replies
    10
    Views
    468

    >but not symmetrical around 1000Hz. You...

    >but not symmetrical around 1000Hz.

    You should use the geometric mean and with that, it is symmetrical.
  47. You might as well get used to the teensy way of...

    You might as well get used to the teensy way of debugging. Lots of print statements, sometimes with a Serial.flush() followed by a delay.
  48. Replies
    18
    Views
    506

    Two questions: I use partitioned fast...

    Two questions:

    I use partitioned fast convolution to greatly reduce filtering delays. Can't partitioning be used for this application?

    If one does use 96 biquad bandpass filters (which seems...
  49. Replies
    18
    Views
    506

    I only looked at it briefly, but that code...

    I only looked at it briefly, but that code appears to be doing a FFT and then combining bins. Not clear why so many people write code without comments.
  50. Replies
    18
    Views
    506

    Agreed, the typical person watching is likely to...

    Agreed, the typical person watching is likely to prefer larger bins and less delay. You can still use the same number of lights, probably most people won't notice the lack of accuracy on the low...
Results 1 to 50 of 500
Page 1 of 10 1 2 3 4