Incompatibility between digiusb and Adafruit NeoPixel

[Honos2014]

Hello there,
I can drive a NeoPixel with the digispark with no problem.
I can use the digiUSB with ease and everything is fine.
But I cannot use both.

include <Adafruit_NeoPixel.h>

//#include <DigiUSB.h>
For the NeoPixel to work I cannot include the DigiUSB lib...
When I compiled the program with both libs it uses 58% of the ram.

Any suggestion?
Thank you

[digistump]

Please try the WS2812 library also included with the Digistump IDE -
NeoPixel is a ram hog and so are the USB based libraries - the WS2812
library uses very little ram and should work along side the USB

On Tue, Mar 31, 2015 at 5:24 AM, Honos2014 notifications@github.com wrote:

Hello there,
I can drive a NeoPixel with the digispark with no problem.
I can use the digiUSB with ease and everything is fine.
But I cannot use both.

#include
//#include
For the NeoPixel to work I cannot include the DigiUSB lib...
When I compiled the program with both libs it uses 58% of the ram.

Any suggestion?
Thank you

—
Reply to this email directly or view it on GitHub
#4.

[Honos2014]

I did managed to make it run with both NeoPixel and DigiCDC. Ram doesn't seems to be the issue.
I did not find the WS2812 library, yet. I'll try when I do find it.
In the meantime, I was wondering about the setup of one of my PC being the culprit...
I will copy the all thing and test that also.
Thank you for your assistance. I'll let you know the result.

[Honos2014]

I have found the ws2812 lib. Testing it...
--EDIT- Here is the code I found -----
#include <WS2811.h>
DEFINE_WS2811_FN(WS2811RGB, PORTB, 1)
RGB_t rgb[1]; //1 for 1 pixel

void setup() {
pinMode(1,OUTPUT);
}

void loop() {
setPixel(0,255,0,0); //set first pixel (zero indexed) to red
updatePixels(); //show the change
}

void setPixel(i,r,g,b){
rgb[r].r=r;
rgb[g].g=g;
rgb[b].b=b;
}

void updatePixels(){
WS2811RGB(rgb, ARRAYLEN(rgb));
}
--- It does not compile
The variables passed in setPixel are undefined... no int, uint8_t
When I define them as uint8_t the program compiles but the the Neopixel (connected to pin 1) doesnt light up, but instead the LED on the board do.

Note: In the folder of WS2812 there is a ws2812.h but no ws2812.c

[sowbug]

This happens to me, too. The repro steps are simple:

1. Create a copy of the strandtest example from the Adafruit Neopixel library.
2. Upload. Confirm it works fine.
3. Anywhere in the strandtest file, even at the very end, add #include <DigiUSB.h>.
4. Upload. Note that nothing works anymore.

I thought that the mere inclusion of a .h meant that DigiUSB.h was redefining something that conflicted with the NeoPixel library. But then I noticed that the .h externs an instance of the DigiUSBDevice class, which contains two monstrously large ring buffers. An an experiment I tried changing #define RING_BUFFER_SIZE 128 to #define RING_BUFFER_SIZE (64), restarted the Arduino application to get it to notice library changes, and found that both libraries now worked together. At this point I searched the web, found this page, and confirmed what @digistump already said earlier in this issue.

For my application, I'm using just one WS2812, so expect that I've already shrunk the NeoPixel instance as much as I can.

I don't yet understand the ramifications of a smaller ring buffer. I bet it has to do with dropped characters if my application doesn't read the buffer frequently enough (on either side). I think this is OK in my case, but it might be annoying in other cases.

TL;DR: try shrinking the DigiUSB ring buffer sizes if you're getting conflicts.

[AidenRay]

In case anyone finds this still relevant, I had the same issue.
By using the WS2812 library, and reducing the ring buffer size to 64, the problem was solved.