Ch340 not initialized on a custom PCB esp32

[Fredalfredo]

Hello to all,
I am currently testing a circuit with a ch340 and an esp32, to program it in USB with Arduino. The ch340 chip is detected but not recognized (see photo), I installed the CH341SER drivers and I can program Arduino nano clones that have a CH340.

translation unregistered USB device

The CH340 chip has a quartz on the schematic that is not used on my board.
I tried the 5v and 3.3v mode of the CH340 chip.

If anyone has any ideas on how to solve the problem or any comments on the schematic it would be great!

[Paul_KD7HB]

@Fredalfredo

The CH340 chip has a quartz on the schematic that is not used on my board.

What is it used for on the schematic? Does it generate the clock signal for the CH340?

[Fredalfredo]

To allow me to use CH340C or CH340G chips, currently, a CH340C is soldered on my PCB. Which I believe does not need external quartz.

[Paul_KD7HB]

I see. And have you checked the modem control pins to see if their voltage is correct?

[Fredalfredo]

I am not familiar with this chip, but I did read some voltage on the pins. I'm not sure about the USB connection either, it's the first time I've used one.

[Paul_KD7HB]

Do the voltages match what the data sheet shows? I would expect some of the modem control pins to be zero volts(ground).

[Fredalfredo]

I tried to solder a USB cable directly on the MODEM and I succeeded in transmitting code to the esp 32 (see diagram). I think I must have a problem with the USB C port.

[Fredalfredo]

After studying the datasheets I finally found my problem, it's an inversion of the connections on the USB C port between D+ and D- on A6, A7, B6, B7.

Thanks a lot Paul_KD7HB for helping me!

The schematic is fully functional and the automatic program transfer works correctly. I'll post it here if someone wants to make his own development board including an esp32, a ch340, and a USB C connector.

[Paul_KD7HB]

Good to know. I am not sure I was any help. but many time problems can be solved by just talking about them. I have helped many programmers in the past by listening to them discuss the problem and then suggesting something to look at.