Serial trouble at startup with TimerCamX and Arduino

  • I'm having wierd trouble with serial debug output with a TimerCamX in the Arduino IDE - serial output sent early in the run is lost, replaced with a string of box characters:


    This is from a demo made from Blink, for simplicity, but my more complex sketch suffers the same problem. I'm running Arduino IDE 2.3.2 with M5Stack 2.1.1, building for M5Stack-Timer-Cam.

    Here's the demo code:

    void setup() {
    // initialize digital pin LED_BUILTIN as an output.


    Serial.println("Starting 1");

    while (!Serial) {
    ; // wait for serial port to connect. Needed for native USB

    Serial.println("Starting 2");


    Serial.println("Starting 3");


    // the loop function runs over and over again forever
    void loop() {
    digitalWrite(LED_BUILTIN, HIGH); // turn the LED on (HIGH is the voltage level)
    delay(1000); // wait for a second
    digitalWrite(LED_BUILTIN, LOW); // turn the LED off by making the voltage LOW
    Serial.println("loop"); // wait for a second