Connecting to Network - botletics/SIM7500-LTE-Shield GitHub Wiki

If you're having trouble getting your device connected to a cell network, this is the place to be. I'll try to keep this as concise as possible and some of these might sound trivial, so please bear with me:

  • Go online and activate your SIM card, whichever SIM you're using
  • Plug the SIM card into the shield and make sure the antenna is properly connected
  • Power the shield via the micro USB connector (this connector is also for communication, so consider using a micro USB cable with data lines!)
  • Make sure the SIM7500 module actually turns on! You should see the green "PWR" light next to the module if it's on
  • Make sure you're able to send AT commands to the module and receive responses in some way, either using the AT command example sketch or by installing USB drivers (preferred, at least for Windows users).
  • Make sure RF is actually enabled on your device by checking with the command AT+CFUN?. If it's 0 you need to switch it to 1 before anything will work! (AT+CFUN=1). If for some reason you can't seem to switch it to 1 and it gives you a CME error, then use AT+CFUN=5 to enable test mode then use the command AT+CFUN=1,1 and it should reboot. After it reboots (wait for the green PWR LED) then try AT+CFUN=1 again and it should work. You could also try resetting the module with AT+CFUN=6 and it should reboot automatically.
  • To check your network connection, run the command AT+CREG? and what you want to see is either "+CREG: 0,1" (home) or "+CREG:0,5" (roaming) indicating that you're connected. With the Hologram SIM you'll see "0,5".

So that's enough debugging and checking if you're connected. Now if you're NOT connected, here's some of my experience using the Hologram SIM card:

  • If your module doesn't automatically connect with the Hologram SIM card, use the command AT+CGDCONT=1,"IP","hologram" (with the proper APN if you're using a different SIM). You shouldn't have to restart the module, but for good measure you can. You can power it off by pulsing the PWRKEY pin of the module (pin 6) to GND for about 1.5-2s, and turn it back on by pulsing the PWRKEY pin again.
  • Furthermore, depending on where you are in the world and what networks are available to you, you may want to use the command AT+CNMP=38 to choose LTE only, or AT+CNMP=14 for 3G only, etc. To see the list of options please see the AT command manual or use AT+CNMP=? to bring up the list.
  • If you still don't automatically connect after setting the things above, check which networks your module sees by running AT+COPS=? (Note that it might take several seconds). You might get a response like "+COPS: (1,"313 100","313 100","313100",7),(2,"AT&T","AT&T","310410",7),(1,"AT&T","AT&T","310410",2),(1,"Verizon","Verizon","311480",7),(1,"T-Mobile","T-Mobile","310260",7),,(0,1,2,3,4,5),(0,1,2)"
  • Once you get a list of networks you can try to manually connect to one of them using a command like AT+COPS=1,2,"310410",7 (Change the six-digit network code with the one you see above)

If you try the things above you should be able to get it connected to a network!

Notes

  • There seems to be a slight issue when using certain SIM cards. For example, while using an AT&T SIM card the AT+CNMP command will not switch to LTE and will automatically be set to WCDMA (3G). When manually switched to LTE (mode 38) the module either won't accept the command or it will accept it but revert later. SIMCom has noted: "The mode apparently cannot be changed with AT&T SIM. My AT&T SIM powers up with 39, not 19. The module will accept the CNMP command and the mode can be changed, but the module will revert to 39 after reset. However, it does work with Verizon SIM (the module will work on Verizon). I tried 2, 38 and 39 with Verizon SIM. The module will remember the mode that was set and come up in the correct mode after reset. From what I see, the issue is SIM card related."