Beetle ESP32-C6 Serial Monitor not working

userHead J-Lips 2024-03-14 16:05:17 256 Views5 Replies

I am using a Beetle ESP32-C6 and am trying to get some simple serial output using Arduino 1.8.19

To get the board to show I used the suggestion of Laurent.VOLPON here

I then used the following settings:

Board: “DFRobot Beetle ESP32-C6” (also tried “DFRobot FireBeetle 2 ESP32-C6”)

USB CDC On Boot: “Disabled” (more on that later)

Other parameters identical to


With these parameters I can write blink without a problem, the board stays connected after uploading the sketch and the code runs directly.


I expanded blink to 

int led = 15;
void setup() {
 while(!Serial) {;}

void loop() {


The serial monitor in Arduino, as well as in PuTTY  don't show anything. In PuTTY I can setup a serial connection but it stays empty.

When I changed USB CDC On Boot to Enabled, as it should be according to the manual (see link above), I started having connection problems. Only after combinations of BOOT + RST on the Beetle the board connects to the PC and uploading sketches works, however the sketch does not run after this (no blinking).

Pressing RST makes the code run, but then the USB disconnects.


I re-installed the drivers (the usbser.sys driver is being used) and tried out a bunch of different settings in Arduino and PuTTY to try to get this to work without success.



2024-03-14 16:33:40

Could you try to delete the “while(!Serial)” line?

This works on my Beetle ESP32-C6


And always set the USB CDC as Enable.



userHeadPic Yeez_B
J-Lips wrote:

Thanks for the fast reply! I tried both with and without the while, with the same result both times. Which Arduino version and OS are you using? I will try to recreate your setup.

2024-03-14 16:44:57
Yeez_B wrote:

I'm using the Arduino IDE 2.2.1 and Windows 11 22H2.

2024-03-14 16:51:36
Yeez_B wrote:


Is your SDK "3.0.0-alpha3" which is same as mine?

2024-03-14 16:53:17
J-Lips wrote:

I got Arduino 2.2.1 and SDK 3.0.0-alpha3 and with that setup it's working just fine! 

Thanks a lot for the assistance!

2024-03-15 06:08:07
4 Replies