NRF52 with BG95M2

Hi,

We’re trying to integrate Quectel BG95M2 chip to NRF52 for quick prototyping.
We have this (https://www.quectel.com/product/umtsevb.htm) board and a module for BG95M2 (https://www.elecomes.com/products/bg95-m5-te-a-catm1-nbiot2-tester-module?variant=36688734552224).

Trying to interface nrf52832 with Quectel BG95M2 chip via UART. By connecting the RX and TX, and sending “AT” command after initializing the UART, the modem doesn’t respond with “OK”, it only echo “AT” back.

The question is, is there anything I’m missing on the connection side? Between the MCU(nrf52) and the BG95? i.e apart from RX and TX if other pins need to be connected as well?

I’m sure I’m missing something simpler, We tried the same way using nrf9160 with nrf52 and it worked fine.

Thanks in advance.

Pls try to send AT from PC to BG95M2 first . if it work fine, it is hardware issue. if not , pls contact with us.

you could use the quectel com tools ( Qcom) , pls kindly download from the below link:

https://cnquectel-my.sharepoint.com/:f:/g/personal/america-fae_quectel_com/EhsaHy3tNy1GvQ70ndked00Bh7cOIQpReF27bDrwbUAtgg?e=bgfJxE

Hi Stephen,

Thanks for responding.

We’ve tried with Qcom, It works fine. The problem is when interfacing with external mcu.

We’ve connected Rx, Tx and can see the data being sent fine once the modem is powered up. But the modem doesn’t respond Ok to AT.

It’d be great if you could shed some light on interfacing the module with external mcu(development kit).

Thanks alot

Start here: https://github.com/RAKWireless/RUI_Platform_Firmware_GCC

Thats a working application using FreeRTOS and Nordic SDK 15, you can set for use with nrf52832, or nrf52840. You will need to configure pin settings, etc for your board, but it works with BG96.

Hi Mathew,

Thanks for sharing this. I suppose you had to translate the uart voltage level to 1.8V from 3.3V for BG95 as well?

Of course. We use the following: TXS0102DCUR.

This ticket can be closed!

Hi Usman_Khan,

I’m working on the same project as you.

you can help me please, I have a communication problem between nRF52840 and the BG96.

the BG96 does not respond to my commands even the ATI command, I have checked the voltage at the GPIO output, they are at 1.8v;

Can you share an example of software with me? I would be a good proponent.

thank you

Hi Dralora,

Are you using the same setup as me?
If yes, have you configured the pins correctly? As stated here (Can we use Voltage translator IC on UMTS&LTE EVB to step down voltage from 3.3 to 1.8 V for communication between external MCU(nrf52) and BG95 Module?)
Have you removed these two resistors(https://forums.quectel.com/uploads/default/original/2X/2/23f15e08532f853e216ae1a19e53a3fc3bf6d8d5.jpeg)?

Given your setup is identical to mine, it worked with simple uart_send and then waiting for response with uart_recv - there wasn’t anything special about the code, the time consuming factor was the hardware configuration which took a while to be sorted out.

Let if know if it worked,

Regards,