SAMD21 (QTPY) dependent on laptop connection for data

[casperdroid5]

I'm using a samd21 (m0) qtpy microcontroller for my project. I connected an eink display to the qtpy. I read the data from an array in the Texts.h file. This worked fine on the arduino pro mini, but it has limit memory, that's why I switched to this mcu. Now i'm using the same code and it works all perfectly fine until I close my arduino ide or connect the controller to an external supply. So somehow it is depending on the pc for data... I am sure that the array is uploaded since the sketch size shrinks when I remove some of the lines in the aray.

The main sketch:

#include "Adafruit_ThinkInk.h"
#include "ArduinoLowPower.h"
#include "Texts.h"

#define EPD_CS      6
#define EPD_DC      7
#define SRAM_CS     3
#define EPD_RESET   5 // can set to -1 and share with microcontroller Reset!
#define EPD_BUSY    -1 // can set to -1 to not use a pin (will wait a fixed delay)


/* Pinout e-ink to seeed XIAO: 
    SRCS = 3
    BUSY = 4
    RST = 5
    ECS = 6
    DC = 7
    MOSI = 11
    MISO = 12
    SCK = 13
*/

int Randomtext = 0;
int Textentries = sizeof(Texts) / sizeof(Texts[0]); 
// 2.13" Monochrome displays with 250x122 pixels and SSD1680 chipset
ThinkInk_213_Mono_BN display(EPD_DC, EPD_RESET, EPD_CS, SRAM_CS, EPD_BUSY);

void setup() {
  
  Serial.begin(115200);
  while (!Serial) {
    delay(10);
  }
  display.begin(THINKINK_MONO);
  pinMode(EPD_RESET, OUTPUT);
  digitalWrite(EPD_RESET, HIGH);
}

void loop() {
  
  display.clearBuffer();
  display.setTextSize(2);
  testdrawtext(Texts[Randomtext = random(0, sizeof(Texts) / sizeof(Texts[0]))], EPD_BLACK); // pick a random text somewhere between 0 and the size of the Texts array
  Serial.print(Randomtext);
  Serial.print(F("Printing text: "));
  Serial.println(Texts[Randomtext]);
  display.display();

  LowPower.sleep(8000);
}
  
void testdrawtext(const char *text, uint16_t color) {
  display.setCursor(0, 0);
  display.setTextColor(color);
  display.setTextWrap(true);
  display.print(text);
}

small part of the .h file:

const char *Texts[] =
{
  // Compliments/personal development
    "You look beautifull today!",
    "Today is the day",
    "Nobody is perfect, but you're so close it's scary",
    "Your voice is my favorite sound",
};

Any idea why the mcu is dependent on the ide's data?

[casperdroid5]

I found the problem:

void setup() {
  
  Serial.begin(115200);
  while (!Serial) {
    delay(10);
  }
  display.begin(THINKINK_MONO);
  pinMode(EPD_RESET, OUTPUT);
  digitalWrite(EPD_RESET, HIGH);
}

Of course it will not work, It waits on a connection with serial aka my computer.