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

Search:

Type: Posts; User: spolsky

Search: Search took 0.00 seconds.

  1. No to both. FastLED is from the old days of...

    No to both. FastLED is from the old days of Arduino Uno... it only supports 24 bit RGB and has lots of integer optimizations (like, it provides very fast integer trig functions). It has some very...
  2. Replies
    21
    Views
    6,861

    Pilot, you are correct that compiler...

    Pilot, you are correct that compiler optimizations (loop unrolls, etc) can make it hard to idle for a certain amount of time.

    On modern chips the CPU may also use pipelining and other...
  3. OctoWS2811 is a library for Teensy that sends...

    OctoWS2811 is a library for Teensy that sends pixel data to WS2812b-type LED strips rapidly, taking advantage of direct memory access (DMA) and parallel output on multiple pins where available. On...
  4. FastLED with Teensy 4.1, fast parallel / DMA output on any pin

    Paul's current github version* of OctoWS2811, when used with Teensy 4.x, can use any pin to drive LED strips in parallel and it's all shockingly fast.

    Here's an example of how to set that up using...
  5. Replies
    21
    Views
    6,861

    The Teensy 4.1 is so heckin' fast you will need...

    The Teensy 4.1 is so heckin' fast you will need much longer noops!

    By experimentation with a scope, I have found that


    void noop() {
    for (uint32_t i=0; i<59; i++) __asm__("nop\n\t");
    }
    ...
  6. Replies
    4
    Views
    254

    You can grab the latest version of the OctoWS2811...

    You can grab the latest version of the OctoWS2811 library from GitHub and you'll be able to use a custom pin list and even put the pins in any order. Here is sample code.

    I have not tried to see...
  7. Replies
    4
    Views
    254

    OctoWS2811 library version

    The OctoWS2811 library has been updated for Teensy 4.0/4.1 (awesome! It's amazing!) allowing ANY pin to be used with high speed DMA and parallel output. It's amazing; I'm using it to drive 16 LED...
  8. Tom, you would need to allocate an array for the...

    Tom, you would need to allocate an array for the leds (you only allocated a pointer).

    Also - did you connect teensy ground to power supply ground?
  9. Thanks! I will submit an issue to the...

    Thanks!

    I will submit an issue to the maintainer of that fastLED documentation.

    With an APA102c directly connected, it does seem to work ok even at 3.3V, but I agree that a level shifter is a...
  10. ah oh... maybe I solved my own problem?...

    ah oh... maybe I solved my own problem? Apparently there's a color code to the pinout card, but the meaning of the colors is not printed on the card any more! By putting the Teensy 4.1 pinout card...
  11. Teensy 4.1 + APA102: which pins support Hardware SPI?

    Easy question, I think ...

    Which pins of the Teensy 4.1 can I use to drive an APA102c LED strip (with data + clock) to take advantage of Hardware SPI support from FastLED?

    The FastLED...
  12. Replies
    2
    Views
    328

    Arg, never mind, I figured it out ... my pointer...

    Arg, never mind, I figured it out ... my pointer arithmetic is all wrong, since each bit is mapped to 32 bits in the bitband region.
  13. Replies
    2
    Views
    328

    Teensy 3.2 bitband?

    Can anyone point me to a simple code example of bitbanding that works on Teensy 3.2?

    I tried this:



    uint8_t st = 0xAA;
    dbgprintf("Address of byte on stack: %x\n", &st); ...
  14. Yep, that is exactly correct. The speed of the...

    Yep, that is exactly correct. The speed of the protocol means that if you want to update 60 times a second for high quality persistence of vision effects, you can only have 552 pixels per strand. On...
  15. Performance measurements with a logic analyzer

    I just wanted to share a debugging technique I came across which most of you will no doubt think is basic, but may be helpful to other newbies like myself.

    I'm working on a project to use a Teensy...
Results 1 to 15 of 15