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  1. N

    Receiving Multiple DMX Universes?

    Tried 41 because I realized it's dividing by the framerate. Still freezes and jumps ahead sometimes.
  2. N

    Receiving Multiple DMX Universes?

    Thanks again. Unfortunately it did not remove the glitches. I went back to >= 13 for both instances. Tried 30 and 60 framerates. Also tried matching the framerate of the controller (40 fps) and one less at 39. And thanks for making that library. Even in 2024, some of us are still using...
  3. N

    Receiving Multiple DMX Universes?

    It still glitches (freeze points with skips) on the Teensy 4.1. I also tried >= 12 and >= 1 with same result. Maybe it will just be a mystery to not worry about. I can use Teensy 4.0 at 528 MHz for longevity in case of heat, since it looks reliable at 150 MHz.
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    Need advice on PCB manufacturers

    OSHPark is very user friendly with great quality. There is a wait time, less options, and they don't do assembly. 4PCB works for my higher volume and assembled boards, but the web site is quite confusing with no previews. I might try PCBway...
  5. N

    Receiving Multiple DMX Universes?

    Here's the test setup with basic DMX circuits (2 isolated in's with daisy chain outs, and 2 outs). The power wires are soldered on the wrong end for convenience, but this doesn't affect signal quality with a small number of LED's.
  6. N

    Receiving Multiple DMX Universes?

    Hi Shawn, I really appreciate you taking a look. I wrote the simplest code for recreating the issue (below). It runs great on Teensy 4.0 even as low as 150MHz. But on the Teensy 4.1 I see glitches on my 8 x 18 test setup that seem to increase with more LED's (additional pretend ones in code)...
  7. N

    Receiving Multiple DMX Universes?

    Ok thanks. Just brief moments of bad data sent to LED's.
  8. N

    Need advice on PCB manufacturers

    I was interested in trying Gerber Labs, but I noticed there's a really bad review and the web site is down now. Maybe these new startups are risky to buy from?
  9. N

    Receiving Multiple DMX Universes?

    So I finally got around to it, and receiving 2 universes works great on the Teensy 4.0 with Octo shield (setRX and jumper to an unused pin). However, on the Teensy 4.1 with Octo shield it occasionally glitches, even with only 1 universe. Not sure if there's a basic fix for this. If not, I...
  10. N

    Receiving Multiple DMX Universes?

    Thanks! It looks like you might be the person who wrote the library. If I'm understanding correctly, the get function does not use a buffer variable and draws from the most recent DMX packet, but the readPacket function does use a specified buffer variable.
  11. N

    Receiving Multiple DMX Universes?

    Is there a simple way to receive multiple universes of DMX without having to use Artnet? In the near future (November), I only need to receive 2 universes per Teensy. Maybe one of the DMX libraries can do this by naming different variables for different Serial ports? It's unclear to me if...
  12. N

    17 or 18-bit PWM on Teensy 4.0 & 4.1?

    It looks like it rounds down before reaching a modulo. 150Mhz / 2288.88 hz = 65534.235 which is greater than 65534 but equal to when the decimal point is thrown away. I haven't tried 2288.85 yet to see what the LED does.
  13. N

    Snooze library -- wake up methods for each mode using Teensy 4.0?

    I've been looking into this yesterday too. In the examples menu there are options that show all the wake up modes. I'm just going to try the code and see what happens.
  14. N

    Ambient Temperature Rating of Teensy 4.0 and 4.1?

    Thanks! Seems like the snooze library can be useful too.
  15. N

    Ambient Temperature Rating of Teensy 4.0 and 4.1?

    Replying to myself again...a quarter of that heatsink is likely lower than 36 C/W, maybe 30 or high 20's because all 4 sides are exposed to fresh air. I'll see if I can find a commercial product that fits...
  16. N

    Ambient Temperature Rating of Teensy 4.0 and 4.1?

    https://www.pjrc.com/teensy/datasheets.html https://www.sparkfun.com/products/16771#:~:text=When%20running%20at%20600%20MHz,support%20for%20dynamic%20clock%20scaling. This 1.1" x 1.1" x 0.6" heat sink appears to be 9 C/W with no airflow...
  17. N

    Ambient Temperature Rating of Teensy 4.0 and 4.1?

    I was wondering if these calcs are accurate: 3.3V * 100mA (@600Mhz) = 0.33 Watts of heat Junction-to-Ambient, no heat sink, natural convection: 40.8 C/W 0.33 W * 40.8 C/W = 13.5 C temperature difference max junction: 95C 95C - 13.5C = 81.5C = 178.7F without heat sink, natural convection...
  18. N

    17 or 18-bit PWM on Teensy 4.0 & 4.1?

    Thanks again! I tested 2288.88 Hz, and I can get the full 16 bits (observed low end) on pins 6, 9, and 10 which use Flex timers.
  19. N

    17 or 18-bit PWM on Teensy 4.0 & 4.1?

    It looks like pin 13 will do 16 bits on the lowest PWM numbers (where it matters) at 2289 Hz but not 2288.82 Hz. Here's code that changes the brightness by typing values into the serial monitor. I was using this on Teensy 4.0 and commented out pins that are on 4.1 but not 4.0 I don't know if...
  20. N

    17 or 18-bit PWM on Teensy 4.0 & 4.1?

    Thanks. This is for a museum installation in a dark room. There will be slow fade ons and fade offs.
  21. N

    TeensyTimerTool

    This all looks complicated and requiring knowledge of interrupts and low-level coding. Is there a simple way to do PWM like AnalogWrite? I'm just trying to do 16,17, or 18-bit dimming of LED's. The default max of AnalogWrite is actually 15 bits, even when resolution is set to 16.
  22. N

    17 or 18-bit PWM on Teensy 4.0 & 4.1?

    Thanks, it looks like I might be able to use the TeensyTimerTool library for GPT. Low-level coding is beyond my knowledge level. With some testing today it appears that both quad and flex are set to 15 bits. The LED's attached to a quad timer only change brightness on odd numbers at...
  23. N

    17 or 18-bit PWM on Teensy 4.0 & 4.1?

    analogWriteResolution()
  24. N

    17 or 18-bit PWM on Teensy 4.0 & 4.1?

    Is it possible to get a few more bits by modifying the file pwm.c or writing a new function? With my basic understanding, it seems that the quad timers are limited to 16 bits and flex timers limited to 15 bits with the standard AnalogWrite function.
  25. N

    Parallel MOSFET's with Different PWM Pins? (Teensy 4.1)

    It's unclear yet whether the main module number has to match up, but it sure looks like the submodule does not need to. I don't have an oscilloscope, but I can measure the temperatures of the MOSFET's and watch the LED strips.
  26. N

    Parallel MOSFET's with Different PWM Pins? (Teensy 4.1)

    After reading about this for hours and doing some testing, it appears that MOSFET's can run parallel as long as duty cycle is the same and the same type of timer channel is used: all Flex A in parallel, all Flex B in parallel, all Flex X in parallel, or all Quad in parallel Does that sound...
  27. N

    Parallel MOSFET's with Different PWM Pins? (Teensy 4.1)

    That is awesome! Thank you so much. I'll dig through that when I have some time. Have to finish a different project at the moment.
  28. N

    Parallel MOSFET's with Different PWM Pins? (Teensy 4.1)

    Yeah, I've done that with a board that has through-hole components, and the extra current burst on the Teensy pin is not too much for just a pair of MOSFET's though it can be harder to estimate lifetime. I could still do that with surface-mount components and get creative with some technical...
  29. N

    Parallel MOSFET's with Different PWM Pins? (Teensy 4.1)

    Only each pair needs synchronized signals. So if 2 MOSFET's have drains tried together and control the red LED's of 1 strip, the gate voltages need to go up and down at the same time, even though they are driven with different Teensy pins (ignoring differences in gate capacitances). Same with...
  30. N

    Parallel MOSFET's with Different PWM Pins? (Teensy 4.1)

    Okay, here's how the boards are wired, with MOSFET drains (to LED strips) corresponding to MOSFET gates (with series resistor and bleed resistor): Red1, Green1, Blue1: PWM pins 3, 4, 5 Red2, Green2, Blue2: PWM pins 6, 9, 10 Red3, Green3, Blue3: PWM pins 11, 28, 29 Red4, Green4, Blue4: PWM...
  31. N

    Parallel MOSFET's with Different PWM Pins? (Teensy 4.1)

    Thanks again. I don't have experience with low-level commands or how to type them into Teensyduino based on reading a microchip manual, but I'll see what I can figure out. Maybe it will be obvious in some examples.
  32. N

    Parallel MOSFET's with Different PWM Pins? (Teensy 4.1)

    Thanks! I'm guessing A and B have to be looked up in the chip datasheet. Some timers have 3 PWM outputs shown on the PJRC web site. The MOSFET outputs are grouped by sets of labelled red, green, blue for specific LED strips. However, if I have to get creative and only use the same timer for...
  33. N

    Parallel MOSFET's with Different PWM Pins? (Teensy 4.1)

    Are the PWM outputs in sync? Even with different timers? I know somebody will say just use the same pin or add a larger MOSFET with a MOSFET driver, but the boards are already made, and I might have to drive more current than they were originally designed for.
  34. N

    KiCAD Frustration

    It appears that KiCAD does not work with servers. The files exist in 2 alternate realities: What KiCAD sees and what Windows File Explorer sees. My head was about to explode until I moved everything to the desktop computer. Now the KiCAD files show up in File Explorer, and the library and...
  35. N

    KiCAD Frustration

    Hey thanks for replying to all that frustration. I figured it out, and your suggestion would have got me there quick. The default grid is 1/1000 of an inch. I set to 1/10 of an inch and it works great! So I guess nobody is trying to push people towards Eagle, although the dots set at 1/10 of...
  36. N

    KiCAD Frustration

    I have a couple questions that might sound silly, but I'm serious about. This is a very helpful forum, and maybe people can speak more freely about KiCAD here. How do I snap to grid in PCBnew? The tips I've found online do not work with the current version, and some of the solutions are just...
  37. N

    16-bit PWM on Teensy 4.0 and 4.1?

    Thanks for the thorough answer.
  38. N

    16-bit PWM on Teensy 4.0 and 4.1?

    Is it possible to fade LED's in 16 bits or higher? The table on this page only shows settings up to 15-bits for Teensy 4.0 and 4.1: https://www.pjrc.com/teensy/td_pulse.html But this page says there are 16-bit timers and 32-bit timers: https://www.pjrc.com/teensy/techspecs.html Also, it seems...
  39. N

    Teensy 4.0 code security?

    You could cut the USB copper traces and pour glue all over it. :)
  40. N

    MIDI All Notes off code takes 2 sec to run can this be fixed?

    That's because MIDI is from the 1980's and it takes about a millisecond to send a note message. Your code sends 2,048 MIDI messages.
  41. N

    APA102/SK9822 LED Strips in Parallel?

    I'm wondering how many LED strips can be in parallel with the output of a Teensy prop shield LC. The level shifters are so tiny, they are hard to read. I think it says "BEG" or "8FQ" on them. Searching isn't bringing up anything. For this application I can lower the clockspeed to about 500...
  42. N

    APA102 Temporal Dithering without Master Brightness?

    Good reads. Thanks. Found this too: https://cpldcpu.wordpress.com/2016/12/13/sk9822-a-clone-of-the-apa102/ The people who make these great products should just hire this guy "Tim" to make their datasheets.
  43. N

    APA102 Temporal Dithering without Master Brightness?

    Okay, I think I understand what you're saying. I should experiment with sending SPI without using the FastLED library and see what happens. https://cdn.sparkfun.com/datasheets/Components/LED/APA102C.pdf
  44. N

    APA102 Temporal Dithering without Master Brightness?

    Thanks Shawn, a lot of good info there. I havent actually tried this yet, though I have used APA102's in the past. I'm just researching at this point. I had thought that global brightness in the FastLED library was like a master brightness control knob at 8-bits, but now it sounds like it...
  45. N

    Teensy 3.6 - USB MIDI INPUT - Random CRASHS

    Some of your code looks very similar to what I posted on this page: http://lights4music.com/instructions.html Did you see this other page? http://lights4music.com/instructions2.html That is USB MIDI to APA102 directly. No DMX. In the first link, I buffered the DMX using serial commands. At...
  46. N

    High Quality APA102 LED Strips?

    Has anybody found high-quality APA102 LED strips from a reputable supplier? (high brightness and rated for 50,000 hours) All I can find is something from a sketchy web site that tries to look like SuperBrightLED's. I know the hobbyist sites like Adafruit and Sparkfun are a step up from...
  47. N

    APA102 Temporal Dithering without Master Brightness?

    Is there a way to do this without dimming all the LED's? I would like to specify each LED individually with 16-bit values of red, green, and blue. Related question: can a Teensy control multiple APA102 strips without having to daisy-chain the clock and data wires?
  48. N

    Storing & Reading Large Arrays on Micro SD Card?

    Thanks again. I'll read up on that. This is new stuff for me. Sounds like the learning curve is not as bad as I thought it might be.
  49. N

    Storing & Reading Large Arrays on Micro SD Card?

    Thank you. I did a quick search, and it looks like there are some discussions on that: https://forum.arduino.cc/index.php?topic=547210.0 https://hackingmajenkoblog.wordpress.com/2016/03/25/fast-efficient-data-storage-on-an-arduino/ I'm guessing there's also a discussion or guide somewhere on...
  50. N

    Storing & Reading Large Arrays on Micro SD Card?

    Megabytes or gigabytes in size. Too large to fit in flash memory.
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