QMI Interface with Sixfab Shields/HATs

QMI Interface with Sixfab Shields/HATs

QMI interface has been mostly asked tutorial for Raspberry Pi 3 and Raspberry Pi 4 with Quectel UC20 / Quectel EC25 attached on our Sixfab 3G-4G/LTE Base Shield v2.

This Tutorial is maintained in our documentation section.

Base Shield
Base HAT
Cellular App. IoT Shield
Cellular IoT HAT

Please submit your technical issues and feedback to the community forum.

This has been tested with Raspberry Pi 4 too.

In this tutorial, we will be demonstrating you the process step by step. Without further ado, let’s get started.

Hardware Prerequisites

  1. Raspberry Pi
  2. Sixfab 3G-4G/LTE Base Shield v2
  3. Quectel EC25 mini PCIe module
  4. LTE antenna (2 antennas are recommended)

Hardware Setup

  1. Plug Quectel EC25 Mini PCIe module to the Sixfab 3G-4G/LTE Base Shield v2.
  2. Connect required antennas to the Quectel EC25 module. (Antenna Connecting Guide will be Available soon!).
  3. Attach the Shield on top of your Raspberry Pi and keep the micro-USB cable disconnected that comes with the Shield.

Make sure you are using the original Raspberry Adapter as your power source.

Software Setup

1. First run update

sudo apt update && sudo apt upgrade

2. Install Raspberry Pi kernel headers.

sudo apt-get install raspberrypi-kernel-headers

3. Check installed kernel headers packet version ls /usr/src
In our case, it is 4.14.79

If you are using Raspberry Pi 4, skip steps 4-7.

4. Now open your browser and go to rpi-firmware github repository commits

5. Here, find out your version and click on <> button to browse the repository at that point in the history.

6. From the link copy the hash as shown in the image below.

7. Now go back your terminal and update rpi in following format. Replace the term <hash> with your hash matching the kernel headers you checked in step 3.

sudo rpi-update <hash>

8. Reboot your Raspberry Pi in order to activate the new firmware

9. After rebooting, download qmi_installer.sh script.

wget https://raw.githubusercontent.com/sixfab/Sixfab_RPi_3G-4G-LTE_Base_Shield/master/tutorials/QMI_tutorial/qmi_install.sh

10. Change the permission of the script.

sudo chmod +x qmi_install.sh

11. Make sure the module is disconnected before running the installer script

sudo ./qmi_install.sh

12. At the end of installation enter any key to reboot your Raspberry Pi and attach the USB cable of the shield.

13. After rebooting goto directory  files/quectel-CM

cd /files/quectel-CM

14. Now run the following command to connect to the Internet.

sudo ./quectel-CM -s internet


./quectel-CM [-s [apn [user password auth]]] [-p pincode] [-f logfilename]

-s [apn [user password auth]] Set apn/user/password/auth get from your network provider
-p pincode Verify sim card pin if sim card is locked
-f logfilename Save log message of this program to file

Example 1: ./quectel-CM
Example 2: ./quectel-CM -s 3gnet
Example 3: ./quectel-CM -s 3gnet carl 1234 0 -p 1234 -f gobinet_log.txt

15. Now you can check you IP using

ifconfig wwan0

16. Further more you may check by pinging

ping -I wwan0 -c 5

Auto Connect on reboot

If you want your Raspberry Pi to automatically connect to the Internet via QMI interface then there is one more step you will need to follow.

1. Get the installation script.

wget https://raw.githubusercontent.com/sixfab/Sixfab_RPi_3G-4G-LTE_Base_Shield/master/tutorials/QMI_tutorial/install_auto_connect.sh

2. Change the permission

sudo chmod +x install_auto_connect.sh

3. Now install the script

sudo ./install_auto_connect.sh

4. It will then ask for APN. Type in your APN and then press ENTER

5. Once you press enter it will create and activate the service.

6. The name of the service is qmi_reconnect. To check if the service is active you can type

sudo systemctl status qmi_reconnect.service

7. If it is working fine then you will be able to see active(running) in green.