Hey,
I need help to interface my BBB with this GSM LTE MODEM. I understand that there is no straightforward answer for this but I’d like some direction at least in this regard
before this, I was able to interface SIM800L with BBB using these (1, 2) resources. I tried to implement the same for the 4g module aswell but it didn’t work with this.
I sent ‘AT’ and I received ‘4’.
I have tried to send AT commands using serial library in python and atcom library aswell but both of them aren’t working.
The beagle bone comes with a USB port can i hookup my module over there and via the beagle bone can I make it a modem ? Is this idea correct ?
if so how do I do it?
Also how to use minicom?
Are you able to use the uart port to connect another device? If you can go point to point it is now an issue with your device sending a correctly formatted string to the modem.
If you have a scope with a decoder you will have much better luck getting this up and running.
As far as the specific modem you are using I don’t have one and don’t have a clue in the world what it takes to get that model running.
Usually a lot of these modems enumerate to multiple USB com ports. I would expect this is the same.
I would imagine it is just a case of setting up PPP correctly. While not Simtel specific this might be a good place to start. https://wiki.archlinux.org/title/Ppp/Mobile_broadband_modem
If the Simtel modems use Qualcom parts then you may be able to use the qmicli command to get a connection. A lot less to configure than with PPP. https://techship.com/support/faq/how-to-set-up-a-simple-data-connection-over-qualcomm-qmi-interface-using-libqmi-and-driver-qmi-wwan-in-linux/
I have used this approach with some Quectel modems. I have never used any Simtel modems.
I’m able to use the same UART port to connect with other devices. (SIM800L) I’m able to interface it with this module.
I will study these , try and get back to you. thanks.
also, do you recommend any particular 4g/LTE modules which are easy to use with beagle bone ( I understand most of them follow similar integration techniques )
Also does anyone know how to use minicom ?
I have always used Quectel modems as there are easier to get in the UK and slightly cheaper.
If you haven’t already I would suggest getting something like one of these - mini PCIe to USB adapter
You can then use any of the mini PCIe modem cards, as long as they use the USB interface on the mini PCIe connector.
I just plugged a Quectel EC21-E using a similar adaptor to a BBB and it recognised the modem with no problems. I am pretty sure it would also connect if I set it up. The kernel also recognises the modem as a Qualcom QMI device and creates the necessary /dev/cdc-wdm0 device so that if the qmicli tool was installed I expect that would also have worked along with PPP
but I dont have anything in /dev, I dont have /wdm0
for now I have managed to connect it via USB & used screen /dev/ttyUSB1 which has helped to operate it with AT Commands.
ok if you re connecting via USB, unplug the modem.
in a terminal window as root type dmesg -w
Wait for the scrolling to stop, then plugin the modem and see what is being detected.
OK so you have 3 COM ports associated with the modem. You will need to check the documentation to see what they are used for
the documentation (pg 39) says,
The A7672S module provides three serial ports: the main full-function communication serial port UART,one common two-cable serial port, and one DBG serial port UART for printing LOG. The moduleisaDataCommunication Equipment (DCE)
Also, I tried using pyserial to try AT commands but it has not returned anything !
Have you read this A76XX Series_Linux_USB_Application Note_V1.00
You will probably need to register an account to be able to download the datasheet,
It details configuring and setting up PPP for the modem
Wow, thank you.
I was just downloading it, I’ll give it a read and try things.
how do I configure minicom?
I was able to setup most of what I want using ctrl+A , Z but how do I send any command?
or will I only be able to send scripts via that ?
In minicom just type. You might need to turn on local echo if the modem doesn’t echo back.
If you just press enter you should get an OK back.
Check to documentation for all of the AT commands. Simtel have a lot of PDFs
Yeah I have access to the AT command documentation that is not the problem but in minicom I’m not able to give any inputs its just blank screen and whenever I use ctrl+A, z I can see other options but still I’m not able to find a way to send AT commands.
try turning on local echo
ctrl+A e
How are you connecting to the BBB ?
