Giga R1 USB and file reading

Hardware GIGA R1
1

Hi everyone,
I came across an interesting problem. I want to read a file from a USB thumb stick which worked perfectly fine with a previous sketch of mine. However, now I modified the code so that the program checks periodically whether a USB stick is attached and initialised or not. This part works fine, but now I get an error and the file cannot be opened and read anymore. I tried a couple of things (switching from if statements to while loops, existence of file, file path), but nothing helped. Any ideas?? :grinning:

I declared all variables globally and created the function:

void usbConnection() {
  unsigned long connectMillis = millis(); 

  if (connectMillis - tUSBCheck >= tUSBCheckInterval) { // Check USB status periodically
    tUSBCheck = connectMillis;
      
    if (!msd.connected()) {
      lv_label_set_text(label, "No USB drive found.");
      static lv_style_t style;
      lv_style_init(&style);
      lv_style_set_text_color(&style, lv_palette_main(LV_PALETTE_RED));
      lv_obj_add_style(label, &style, 0);

      Serial.println("MSD not connected");
      usbConnected = false; // Update flag to false if not connected
      msd.connect(); // Attempt to connect to USB drive
      delay(500);
    }

    else if (msd.connected() && !usbConnected) {
      lv_label_set_text(label, "USB drive found.");
      static lv_style_t style;
      lv_style_init(&style);
      lv_style_set_text_color(&style, lv_palette_main(LV_PALETTE_GREEN));
      lv_obj_add_style(label, &style, 0);

      Serial.println("MSD connected");
      usbConnected = true; // Update flag to true if connected
    } 
  }
}

I call this function in
void loop() { usbConnection(); }

and to read the file on the USB stick, I created:

void btnLoadFileClicked(lv_event_t * e) {
  Serial.println("Load file button clicked");

  if (!msd.connected()) {
    Serial.println("USB not connected. Please connect a USB drive.");
    return;
    }

  // Opening .txt file for loading of parameters
  delay(2500);
  settings = fopen("/usb/settings.txt", "r"); 

  if (settings) {
    Serial.println("Opened file");
// logic for file handling

    fclose(settings);
    Serial.println("Closed file");

    } else if (!settings) {
    Serial.println("Failed to open file");
  }
}

I'm always getting "Failed to open file" in the serial monitor... :wink:

Best, Lea

2

I am wondering if the problem actualy occurrs because the USB port is basically busy doing something else (msd.connected()) and thus the file cannot be opened. I also tried changing/adding/removing delays in the code snippets.