ESP32 C3 UART USB problem

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stefan.erni
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ESP32 C3 UART USB problem

Post by stefan.erni »

Hi to All

I have the ESP32 C3
I can compile and download to target and it's running
(no press of reset and boot)
I use the GPIO18 and GPIO19 like the schema for UART/USB
But as soon as I switch on the Uart in FC10 and flash I can not connect anymore the ESP to the computer,
there is no com port anymore also not in the terminalprogram.
For the next flash I need to press reset and boot first

https://docs.espressif.com/projects/esp ... ction.html
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BenR
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Re: ESP32 C3 UART USB problem

Post by BenR »

Hello,

It looks like on that device there may not be a UART to USB bridge IC and so they expect you to use the USB peripheral as the comms. We don't currently support the USB on the ESP32 devices but I could add it to the list to investigate if that would help.

stefan.erni
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Re: ESP32 C3 UART USB problem

Post by stefan.erni »

Hi Ben

UART to USB bridge IC are often relatively large so that they are missing in the very small board.
Yes, that would be very good if it follows in a few weeks.
I am always ready to test it.
I think we will also look at the App Developper to have an easy to use and very fast USB connection for the ESP32 (without UART to USB bridge).

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Re: ESP32 C3 UART USB problem

Post by BenR »

Hi Stefan,

I've made a good start with this now and aim to finish it off next week in between doing other things.

Atm it's looking very good and easy to implement and will become part of the standard USB Serial component.

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Re: ESP32 C3 UART USB problem

Post by stefan.erni »

Hi Ben

How can I use the standard USB component?

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Re: ESP32 C3 UART USB problem

Post by mnfisher »

Quick question on this - does the chip output the usual stream of debug info to USB (if so then there is a link to USB as stands)

Martin

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Re: ESP32 C3 UART USB problem

Post by stefan.erni »

Hi Marrtin

No stream of debug info to USB possible...

I can't use USB with Atom S3 with display either.
The Pin's go direct from ESP32 to USB pin
A USB component would be useful for transferring data.

I don't have any options with Bluetooth either.
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stefan.erni
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Re: ESP32 C3 UART USB problem

Post by stefan.erni »

Hi Ben
Ben wrote
I've made a good start with this now and aim to finish it off next week in between doing other things.
Atm it's looking very good and easy to implement and will become part of the standard USB Serial component.
Is there already a way to use USB with the C3 and AppDeveloper?

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Re: ESP32 C3 UART USB problem

Post by mnfisher »

Did you get the S3 to work?

Just tested with a C3 and using the JTAG / USB link and printf("string"); works well with this variant too! So you could output to USB and 'catch' the data in App Developer here too?

Note that you can use printf with optional arguments for example printf("Value = %d\r\n", FCL_VAL); to print an integer value.

Martin

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Re: ESP32 C3 UART USB problem

Post by stefan.erni »

Hi Martin

I think only the S3 has this option, a built-in UART to USB bridge.
This is not possible with the C3. I should also be able to reach 921600 baud and send and receive integer arrays to the AppDeveloper.
At the moment, I am still using the ESP32 WROOM, but I would also like to use hardware with the C3 and S3.
These are small and require less power.

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