Communication with ESP-AT (ESP32-WROOM-32E)

[ali_joubir]

we want to try connect ESP32 with STM32 via UART using the ESP_AT
after flashing the esp32-wroom-32e with esp-at firmware (ESP32-WROOM-32-V2.2.0.0), the output from UART0(USB in dev-ket) is as expected (figure1).

figure1.png (233.94 KiB) Viewed 2462 times

But we couldn't communicate with the ESP32 via UART2, we try to send "AT" & "AT+GMR" with no reply from the esp (figure2).

figure2.png (2.29 KiB) Viewed 2462 times

note that we try that with different UART transceivers (STM32, ARDUINO UNO, FTDI-CHIP)
what could we be doing wrong?

[ESP_Sprite]

Are you sure you have the line endings correctly? AT requires CR+LF iirc.

[ali_joubir]

Hi thanks for the reply, I solved the problem, I'm not sure if that was the problem but when I switch from arduino to a 3v3 ftdi it work
I think the 5v arduino couldn't communicate with esp32 without a voltage translator