ESP32 WROVER not responding for AT commands.

[senthilkumar]

Hi,
In my board i have ESP32 wrover which has to communicate with my controller using AT commands.I have uploaded AT firmware using flash downloading tool successfully.unfortunately there is no response from ESP32 for AT commands i sent from PC for testing purpose.But i receive garbage values continuously from esp sometimes or no response at all.so i tried uploading AT firmware again but i couldn't connect my ESP with flash downloading tool. It shows error message "chip sync error failed to connect to esp timed out waiting for packet header".

I have checked voltage for ESP is 3.3v and baudrate is 115200 (both end).

flash download tool setting.
SPI Download
crystal-- 40MHz.
SPI mode--DIO.
SPI speed--40MHz
Flash size--32Mbit
Baudrate--115200.

I couldn't find out reasons behind these issues.

Thanks.

[Helen L]

Have you tried the ESP Flash Download Tool? Maybe you can erase the entire flash firstly and then download the firmware into it.

After downloading the ESP32_AT Bin, in the "factory" folder, there is an AT bin for ESP32-WROVER, you can download it into the address 0. AT baud rate is 115200.

[senthilkumar]

Hi,

yes, I tried erasing entire flash using flash download tool but i cant connect with esp32.it shows error "chip sync error esp_sync blocking"

Thanks.

[TyraMisoux]

You pulled IO0 to L when resetting? Sounds like you did not manage to enter bootloader-mode.

I found here from Google since I have same problem: Flashing works fine, Even erased whole flash (so UART0 seem to work fine). But there is no response to AT-Commands on UART1.
from UART1 I see a "ready" after reset and I receive an ECHO for everything I enter but when pressing "Enter" exactly NOTHING happens. No "OK" and no "ERROR"...
Even used a new ESP32 to ensure it is fine.

Whats wrong here?

[shalinipatil@123]

Hello
ESP WROOM-32 is not respoding to AT commands what should i do? anyone please tell me require hardware setting how to flash download. basic connection of EN,3V3,TX,RX,GND are done .

[nopikus]

Same problem here. Module respond as ready - no commands or echo
Reply to myself - commands expecting (!!!) exact line ending (CRLF by default )