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WebSerial comes with a single callback called onMessage. It's responsible for notifying your firmware whenever it has received a command/message from user via webserial terminal.

If the callback is not registered, then the command received from terminal is simply discarded.

Example Usage

#include <WebSerial.h>

void setup() {

/* Attach Message Callback */
WebSerial.onMessage([&](uint8_t *data, size_t len) {
Serial.printf("Received %lu bytes from WebSerial: ", len);
Serial.write(data, len);

void loop() {