SPI OLED and NeoPixel Ring Conflict

[thechill]

Hi Everyone,

I've got a Flora that is setup to output on an OLED display, as well as a NeoPixel Ring; but it can only output one or the other:

Parts:
Neopixel 24 Ring: https://www.adafruit.com/products/1586
128x64 SPI OLED Display: https://www.adafruit.com/product/661

The pins are setup as follows:
Ring GND -> Flora GND
Ring 5V -> Flora VBatt
Ring Data In -> Flora D12

Flora is USB powered for now

OLED Vin -> Flora 3.3V
OLED GND -> Flora GND
OLED DATA -> Flora D6
OLED CLK -> Flora D3
OLED DC -> Flora D10
OLED CS -> Flora D1
OLED RESET -> Flora D2

I can run the ssd1306_128x32_spi sketch no problem; and I can run the strandtest sketch, no problem; but I can't get both to output at the same time if I combine the sketches into one. Depending on which one I initialize first in the sketch, the other will remain dark. The code continues to run as if the OLED or ring are displaying as normal.

Hypothesis: Insufficient power or memory on the flora. Possibly a conflict with the pins I'm using. Or, worst case, my code.

Thanks!!

[Franklin97355]

It could be a memory issue. Could you post your code ?
Please use the code button "</>" or

Code: Select all

 tags when posting code to the forums.

[thechill]

Code below. Again, I can run the sample codes independently (strandtest, ssd1306_128x32_spi) just fine on the same setup.

Note that using the below, the OLED works fine, but the LED ring won't respond to any setpixelcolor commands. I tried multiple pixel addresses (0-23) and RGB codes. Interestingly, if I run a piece of LED ring code beforehand (i.e., set the LED ring to all red), it retains this in memory and continues to show the red LED ring pattern even when I run the code below after it. That makes me think it's a memory issue rather than a power issue.

Code: Select all

// SPI OLED Reqs
#include <SPI.h>
#include <Wire.h>
#include <Adafruit_GFX.h>
#include <Adafruit_SSD1306.h>

#define OLED_MOSI   6
#define OLED_CLK   3
#define OLED_DC    10
#define OLED_CS    1
#define OLED_RESET 2
Adafruit_SSD1306 display(OLED_MOSI, OLED_CLK, OLED_DC, OLED_RESET, OLED_CS);
#define NUMFLAKES 10
#define XPOS 0
#define YPOS 1
#define DELTAY 2
#define LOGO16_GLCD_HEIGHT 16 
#define LOGO16_GLCD_WIDTH  16 

// NeoPixel Ring Reqs
#include <Adafruit_NeoPixel.h>
#define PIN 12 
Adafruit_NeoPixel strip = Adafruit_NeoPixel(24, PIN, NEO_GRB + NEO_KHZ800);

// SETUP
void setup()   {                
  Serial.begin(9600);
  display.begin(SSD1306_SWITCHCAPVCC);
  display.clearDisplay();
  // Clear the buffer.
  
  // The following won't work
  strip.setPixelColor(1, strip.Color(255,255,0));
  strip.show();
  delay(100);
}

// MAIN
void loop() {

  // Display on the OLED, this works
  display.setTextSize(1);
  display.setTextColor(WHITE);
  display.setCursor(0,0);
  display.println("This works, but my LED doesn't");
  display.display();
  delay(100);
  
  // And this won't work here either
  strip.setPixelColor(2, strip.Color(0,255,0));
  strip.show();
  delay(100);
  
  display.clearDisplay();
}

[Franklin97355]

You might take a look at this on Arduino memory management

[thechill]

Well, my sketch compiles at 15K, well under the 28K flash limit with a bootloader. And the SRAM utilization according to this shouldn't be more than 1.1K, which is well under the 2.5K limit...

Not sure what it could be then...

[adafruit_support_rick]

The compiler's estimate of SRAM usage isn't a very useful number. You want to include the freeRam function from the tutorial, and call it at the end of setup()

[adafruit2]

Hmm that is odd. But not sure what it could be...it *might* be RAM but 24 pixels isn't very much. Do you have a logic analyzer or scope? would be useful to see if it even sends the data out the neopixel pin

[thechill]

I get freeRam() reading back end of setup at 1432.

I unfortunately don't have a logic analyzer or a scope; I could probably get a general "something is happening" on my multimeter, but that's it.

Is this something you guys have seen before?

[pburgess]

Just missing a strip.begin() in the setup() function, that should take care of it.

[thechill]

: ( Embarrassing.

Thank you!!