USB Serial port


When I start my computer with the Arduino Nano Every plugged in to the usb port, I can receive data from the arduino, but I cannot transmit until I unplug and plug it again.

I'm using Windows 10 and a serial terminal software.

I have tested it with several computers and Nano Every boards.

I have tested with the osciloscope that in the TX pin of the ATSAMD11 there is no data. If I reset the ATSAMD11 (Pin 18 to GND), it works.

This is my sample code to test it.

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

void loop()
static long t=millis();
static int n=0;

if(millis()-t > 1000)
t = millis();
digitalWrite(LED_BUILTIN, n++ & 0x01); // turn the LED on/off every second
Serial.println(n); // Send any data
if(Serial.available()) // If there is any data in the serial port
char b =; // Read the data
Serial.print(b); // Send the data

Thanks for the sugestions


Fixed after update SAMD11 to MuxTO 1.0.6