I’m using the EG915U-EU module for my project based on the ESP32-S3. I’ve already written code that receives incoming call data via UART, parses it, and forwards it further — everything works fine.
However, I also need the GSM module to handle internet data transmission. As far as I understand, I can’t use the same UART for both CLIP (caller ID) and internet connection at the same time, right?
Could you please advise the correct way to implement this? Thanks in advance.
Hi,
The EG915U-EU can handle both call information (e.g., RING, +CLIP: URCs) and IP data traffic over the same UART via AT commands. This means there’s no need for a second UART.
ESP32 sends AT commands to the modem via the UART.
It sends RING and +CLIP: messages as URCs (unsolicited responses) for incoming calls.
It simultaneously handles internet traffic via AT-based TCP/UDP sockets (such as AT+QIOPEN, AT+QISEND, AT+QIRD).
You can’t switch to transparent or PPP mode, as these modes convert the UART entirely into a data channel, and URCs are cut off.
In your case, using a non-transparent (AT-Socket) is fully compatible.
Dear customer,
We apologize for the delayed response.
Could you please confirm if the issue has been resolved?
Regards,
Fazrul Redzuan