ESP32 Forum

Hello there!!

I need some basic information from more experienced developers whether stuff I'm trying to do is even possible or not. I tried to connect ESP prog to devboard identical to this one:

https://dl.espressif.com/dl/schematics/ ... 80607a.pdf

with wrover-module-b installed.

I tried to use esp-prog because I want to both download and JTAG debug with single kit. So far debugging works but I can not connect to UART. Onboard usb-uart works fine. I just cannot get esp-prog ftdi chip to connect with devkitc. I have a feeling I'm doing sth stupid here.

Is this even possible to use ESP-PROG when bard has USB-to-UART installed on board? Or should I just try to use on-board uart converter and just JTAG interface from ESP-PROG? But then how do I connect power lines? I mean devki-c will get its power from USB. ESP-prog as well (from different usb-port), what do I do with 3.3V pin on esp-prog? Documentation from devkit C states that only one power source should be used (either USB or 3.3v pin) not both.

Thanks for you help in advance. I could really use it. I've wasted many hours on this and still no progress made.
Lukas

So basically the problem is that every time I want to download via UART i need to disconnect JTAG. I'll just try to flash program via JTAG today and see if it works. I guess this would be solution to my problems.

Hi Lukas!

Did you manage to solve that issue with the ESP prog? I am having the same problem and I don't find any solution...

Thanks in advance.

Miguel

Can you share any schematic or diagram of what you're actually connecting?

The ESP-PROG has a usb-to-serial chip FT2232 on it. The DevKitC also has usb-to-serial CP2102. So you should only be using one at a time. If you tried to use both, they are both trying to put signals onto the TX/RX lines to the esp32, they will fight eachother and you'll just have garbage data.

There are some PWR jumpers you'll need to set on the ESP-PROG, have you checked those?

https://github.com/espressif/esp-iot-so ... uide_en.md

The ESP-PROG has this Program Interface connector. This basically duplicates exactly what the CP2102 on the devkitc does. So this is the connector you should be using for programming / uart.


The ESP-PROG JTAG interface connects to ESP_TMS, TCK, TDO, TDI, similar to SPI with CS, CLK, MOSI, MISO.


It looks like this is the typical JTAG connection:

GPIO12 — TDI
GPIO15 — TDO
GPIO13 — TCK
GPIO14 — TMS

https://medium.com/@manuel.bl/low-cost- ... bee39e508b

This is what I am using to debug / DL code on ESP32 with ESP-PROG.

I always forget if you need to do that on the ESP-Prog, but maybe try reversing TxD and RxD? Also, I assume you made the modifications on the DevkitC mentioned in the PDF as well? Also note that the ESP-Prog typically shows up as *two* serial ports; you will need to use the 2nd of the two.