Error Flashing new KCS firmware using ESP32 Download Tool

[steven22]

Hi everyone, I'm new to Kincony products and this forum. I recently bought a Kincony A2V3.1 board to test these products and their integration with Home Assistant.
Once the board arrived, I connected it to my router via LAN cable, but I cannot see any IP address on the A2V3 screen, nor can I find it on my network.

For this reason, I tried to reflash the KCS v3 firmware using ESP32 Download Tool V3.9.2 and entering download mode (turn off → press S2 button → turn on power → release S2).
However, when I press "start" on the ESP32 Download Tool, I get this error:

Code:

1 kill
test offset :  0 0x0
case ok
test offset :  0 0x0
case ok

Uploading stub...
Running stub...
[2025-07-12 09:22:45,885][ESP8266Loader_spi[1]][espDownloader.py][line:586][ERROR]: ESP32 Chip stub error esp_stub_and_set_baud.
no log file output ...

I already tested it with different USB cable, different PC and different power supply. But getting always same error.

Here a screenshot from ESP32 Download Tool V3.9.2:
   


Can you please help me debugging this issue?

regards,
Stefano

[admin]

can you change a usb-c cable.

[steven22]

Hi,

I tested with 3 different USB-A to USB-C cables and with a USB-C to USB-C cable, but same results.
Also tested all cables from different PC.


regards,
Stefano

[steven22]

now I was able to flash espHome via espHome web installer. But still cannot install KCS firmware using ESP flash tool.
I need KCS to test 4G communication via sim7600E module.

[admin]

take a photo of your board, how you wire and what power supply you are using.

[steven22]

I'm powering it using a 12V 1A power supply.
Also tested with a 9V 1A before.

       

[admin]

please change another power supply for testing. we usually use 12v 2A

[steven22]

now I also tested a 12V 2A power supply, but still same problem flashing KCS firmware.
Are there also other flashing tools I could try?

[steven22]

[SOLVED]

Finally, I was able to flash KCS firmware using ESPHome web flasher.

[admin]

ok, good.