Using ESP-IDF for C programming on WiPy

[EngeenerAtendee]

Hi!

Some time ago I've decided to leave micropython and start development in C (University requirements..). As we all know WiPy 3.0 is based on ESP32, so I've tried to use ESP-IDF.
I got following error:

A fatal error occurred: Failed to connect to ESP32: Invalid head of packet (0x08)

I'm using WiPy 3.0 with FTDI USB converter on breadboard. I've installed all drivers for ftdi. Tried using Pycom branch of ESP-IDF. Still same problem.

Converter is connected to default pins on board.

Any ideas, why it is not working?

Maybe I should buy Expansion Board?

[robert-hh]

@EngeenerAtendee That#s good. However, if GND is connected between UART converted and WiPy, it should not matter on which side you connect P2 to GND.

[EngeenerAtendee]

@robert-hh
You were right!
I achieved success after changing UART converter GND to WiPy GND. Now it works. Thanks!

[robert-hh]

@EngeenerAtendee If you connect P2 (which is GPIO0) to GND, open a terminal emulator (e.g. putty, .. ) with 115200 baud and push reset, you should see a message like:

rst:0x1 (POWERON_RESET),boot:0x3 (DOWNLOAD_BOOT(UART0/UART1/SDIO_REI_REO_V2))
waiting for download

If not, the device is not in download mode or connected wrong.

[EngeenerAtendee]

@robert-hh

No difference. Timeout in firmware update mode and Invalid head of packets in normal mode.

[robert-hh]

@EngeenerAtendee Try to lower the baud rate with:

make ESPBAUD=230400 flash

[EngeenerAtendee]

@robert-hh
In firmware update mode I have timeout problem.
I've connected P02 to GND and pushed reset. LED stopped blinking. I've run "make flash" and this error occurred:

/dev/cu.usbserial-AC0210YS failed to connect: Failed to connect to ESP32: Timed out waiting for packet header

[robert-hh]

@EngeenerAtendee You have to connect GPIO0 (=P2) to GND and push reset, to set the ESP32 into firmware update mode. Then firmware upload should work.