SPI pin selection for SD

[bfgelectronics]

I want to store some data on a SD card an i used this snippet of code to initialise the SD card, but it seems like the Pico freezes/crashes here :

  SPI.setRX(12);
  SPI.setCS(13);
  SPI.setSCK(10);
  SPI.setTX(11);
  SD.begin(13);

I know that the Pico freezes here because i also have an I2C OLED display connected that shoud display something in normal conditions, but with that snippet it stays black
For context, here is my setup() :

void setup() {
  Wire.setSDA(16);
  Wire.setSCL(17);
  Wire.begin();

  pinMode(18, INPUT_PULLUP);
  pinMode(19, INPUT_PULLUP);

  Serial.begin(9600);

  SPI.setRX(12);
  SPI.setCS(13);
  SPI.setSCK(10);
  SPI.setTX(11);
  SD.begin(13);

  if (!display.begin(SSD1306_SWITCHCAPVCC, SCREEN_ADDRESS)) {
    Serial.println(F("SSD1306 allocation failed"));
    for (;;) {}
  }

  display.setTextColor(SSD1306_WHITE);

  display.clearDisplay();

  attachInterrupt(digitalPinToInterrupt(19), increment, FALLING);
  attachInterrupt(digitalPinToInterrupt(18), decrement, FALLING);
}

[earlephilhower]

You are not setting legal pins for the SPI interface, and the Pico is panicing. You could probably use SPI1 with those pins. Fix the pinout per the usual diagram (borrowed from Adafruit):

[Andy2No]

@bfgelectronics If the screen initialisation fails, you probably won't see the message on the serial console, because it happens too soon after booting up - it takes a second or two before the serial monitor starts responding, unlike when using things like the Uno or Mega 2560.

Try adding a short delay at the start of setup, maybe blinking the LED for a couple of seconds. Also, make that part of the forever loop, after trying to report the error:

  if (!display.begin(SSD1306_SWITCHCAPVCC, SCREEN_ADDRESS)) {
    Serial.println(F("SSD1306 allocation failed"));
    for (;;) {}
  }

Change the for loop to something like this:

  pinMode(LED_BUILTIN, OUTPUT);

  if (!display.begin(SSD1306_SWITCHCAPVCC, SCREEN_ADDRESS)) {
    Serial.println(F("SSD1306 allocation failed"));
    for (;;) {
       delay(200); digitalWrite(LED_BUILTIN, 1);
       delay(300); digitalWrite(LED_BUILTIN, 0);
    }
  }

[Andy2No]

@bfgelectronics Also, since those pins can only be used for SPI1, I think you need to change this:

  SPI.setRX(12);
  SPI.setCS(13);
  SPI.setSCK(10);
  SPI.setTX(11);

To this:

  SPI1.setRX(12);
  SPI1.setCS(13);
  SPI1.setSCK(10);
  SPI1.setTX(11);

I don't know if the standard SD library works with SPI1 though. You might need to find a different library to do it, or just use the SPI0 pins instead.

[bfgelectronics]

Thanks to everyone for support!
@Andy2No yep, i tryed the and the SD library doesnt work with the SPI1, but moved the SD card to some SPI0 pins and now it works!

  SPI.setRX(4);
  SPI.setCS(5);
  SPI.setSCK(2);
  SPI.setTX(3);
  SD.begin(5);

[Andy2No]

@bfgelectronics Cool. I'm glad you've got it working. It's good to have it confirmed, that the SD library needs SPI0 too.

[earlephilhower]

@bfgelectronics I have modified the SD.begin() call to include an optional SPI port. (edited)

You can give it as try with your original wiring, but you'd need to change the set calls to:

  SPI1.setRX(12);
  SPI1.setCS(13);
  SPI1.setSCK(10);
  SPI1.setTX(11);

and then call

SD.begin(13, SPI1);