First ESP32-C6 based board - USB problems

Other Hardware Hardware Development
1

Hi,

I ordered my first simple ESP32-C6 board of my own design from a chinese manufacturer (PCBWAY) and received the two boards this week. They look nice, and they boot ok, but the USB connection fails.

Windows indicates that the USB device was not recognized and Ubuntu dmesg reports "ERROR: device descriptor read/64, error -32".

It is driven from the USB 5V power, and when I plug it in my 3.3V powered LED lights up, and the board consumes around 30mA from the USB 5V. When I push my button that pulls the EN signal to ground the power drawn is reduced to around 8mA.

To me this indicates that the MCU starts and does something, but since I have not been able to connect any serial communication to it yet I don't know what.

I am a newbie in the MCU-PCB area, so I did not expect everything to work, and would very much appreciate any help on finding out how I can get the connection up and running.

I realized that I have missed one important thing, as I did not connect neither GPIO8 and GPIO9 pins, which control the boot sequence, so today I added a pull-up to GPIO8 and a pulldown to GPIO9. However, the behavior seem similar even after this update.

Kicad PCB and schematic uploaded.

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Any help / feedback appreciated.

2

I just want to say I am very impressed. Most first-time posters are working on getting Hello World to work; making your own board is a giant step up. Good luck.

1 Like
3

Please run a continuity check. Take a multimeter and see if there is any broken trace.

4

If you don't have a scope, I would:

Write a small program that toggles the USB outputs. Put an LED or multimeter on the USB-C data pins and see if they are following the program commands.
i.e. ON 20 seconds, OFF 10 seconds or similar. This will verify the connections are functional.

5

I would do that except I cant flash the unit since the USB is not working :slight_smile:

6

I'll do some scraping today and try to measure what I can

7

DUH (on my part).

Another (hopefully more achievable). Do you know if pin 17 and 18 are actually connected? If not; when powered, put 5V in series with a 10k resistor into the USB data line. If pin17 rises to ~ 4V (3.3 +0.7) then it is connected to the chip, if it goes right to 5V then it is not and you can complain to PCBWAY.

8

Thanks. I'll check it.