Quectel 5G-Modem doesn't work at all

[tom]

@Jerry-Lin They can be, it just depends on the carrier. We always test here with Google Fi IoT SIM cards, they're super easy to setup and cheap

[Jerry Lin]

Cool, my carriers are AT&T and Xfinity Mobile. What I should I mention to them for my application? Just IoT or any specs that you know about?

So, the log:

voxl2:~$ quectel-CM -s nxtgenphone
[09-10_01:27:54:793] Quectel_QConnectManager_Linux_V1.6.0.24
[09-10_01:27:54:795] Find /sys/bus/usb/devices/2-1.1 idVendor=0x2c7c idProduct=0x800, bus=0x002, dev=0x003
[09-10_01:27:54:795] Auto find qmichannel = /dev/cdc-wdm0
[09-10_01:27:54:795] Auto find usbnet_adapter = wwan0
...
[09-10_01:58:12:576] requestSetupDataCall message timeout
[09-10_01:58:12:576] requestSetupDataCall err = 110
[09-10_01:58:12:576] try to requestSetupDataCall 60 second later
[09-10_01:59:12:615] requestSetupDataCall QMUXResult = 0x1, QMUXError = 0x1a
[09-10_01:59:12:615] try to requestSetupDataCall 60 second later

looks a SIM card issue to you? Or what else (e.g. commands or wiring) can I try to get 5G connected?

[tom]

@Jerry-Lin I would mention IOT as well as the modem you're using "Quectel RM502Q-AE". I know when I was first working with this modem that some carriers didn't yet support but that was a long time ago so I'm guessing that has changed

[Jerry Lin]

OK, will get to carries to see if I can move forward with the existing SIM cards. If not, will try Google Fi IoT SIM cards.

Thanks for the advice!!!

[Jerry Lin]

I

• checked with an AT&T store and they provide SIM card for phone only.
• then googled around and found several attempts using Quectel MODEM with AT&T SIM card and AT commands were used for debugging.
• searched in ModalAI Forum and found some AT commands for the model.
• tried but got only ERROR

  voxl2:~$ echo -ne "AT+QNWPREFCFG="mode_pref",LTE:NR5G\r" | busybox microcom /dev/ttyUSB2
  AT+QNWPREFCFG=mode_pref,LTE:NR5G
  ERROR

• did voxl-configure-modem again to see if AT commands can be used and found the same command:

  Sep 25 02:41:22 m0054 voxl-modem-start[8392]: qrb5165 based hardware detected...
  Sep 25 02:41:22 m0054 voxl-modem-start[8392]: \Setting mode preference to LTE / 5G
  Sep 25 02:41:22 m0054 voxl-modem-start[8392]: AT+QNWPREFCFG="mode_pref",LTE:NR5G
  Sep 25 02:41:22 m0054 voxl-modem-start[8392]: OK
  Sep 25 02:41:23 m0054 voxl-modem-start[8392]: Initalizing cellular connection...

• After 7 minutes I saw: no lease, failing. Well, at least, it tried to lease.

  Sep 25 02:48:49 m0054 voxl-modem-start[8392]: udhcpc: started, v1.27.2
  Sep 25 02:48:49 m0054 voxl-modem-start[8392]: No resolv.conf for interface wwan0.udhcpc
  Sep 25 02:48:49 m0054 voxl-modem-start[8392]: udhcpc: sending discover
  Sep 25 02:48:52 m0054 voxl-modem-start[8392]: udhcpc: sending discover
  Sep 25 02:48:55 m0054 voxl-modem-start[8392]: udhcpc: sending discover
  Sep 25 02:48:58 m0054 voxl-modem-start[8392]: udhcpc: sending discover
  Sep 25 02:49:01 m0054 voxl-modem-start[8392]: udhcpc: sending discover
  Sep 25 02:49:04 m0054 udhcpc[10399]: wwan0: configuration failed: leasefail:
  Sep 25 02:49:04 m0054 voxl-modem-start[8392]: udhcpc: no lease, failing

• All of sudden, I saw lease obtained with an IP provided:

  Sep 25 02:49:04 m0054 voxl-modem-start[8392]: udhcpc: started, v1.27.2
  Sep 25 02:49:05 m0054 voxl-modem-start[8392]: No resolv.conf for interface wwan0.udhcpc
  Sep 25 02:49:05 m0054 voxl-modem-start[8392]: udhcpc: sending discover
  Sep 25 02:49:05 m0054 voxl-modem-start[8392]: udhcpc: sending select for 10.194.135.84
  Sep 25 02:49:05 m0054 voxl-modem-start[8392]: udhcpc: lease of 10.194.135.84 obtained, lease time 7200
  Sep 25 02:49:05 m0054 voxl-modem-start[8392]: Too few arguments.
  Sep 25 02:49:05 m0054 voxl-modem-start[8392]: Too few arguments.

• I was not sure about the impact of Too few arguments error, though.

Well, with an IP address, I tried to:

• ping
• ssh

Unfortunately only responded with timeout messages.
Wondering if I really have the Internet access, I did ifconfig wlan0 down and the ping google.com from voxl. It was still responded !!!

Hmm, how about continue Connecting to QGC over 5G instructions?

• With Tailscale VPN installed, I was able to ssh to the drone using the VPN IP address!!!
• With QGroundControl setup, I was able to see the drone statuses and statistics using the VPN IP address!!!

That means I can control the drone even it is hundreds of miles away!!!

Millions of thanks for great help @tom and @Vinny !!!!!!!!!!!

Still with Too few arguments error, I am not sure how good the 4G/5G connection would be. Will experiment more to figure out. However, if you guys know anything can be improved, please let me know.

[tom]

@Jerry-Lin You can ignore the "Too few arguments" message, that comes from lower down in the quectel driver, it shouldn't cause any issues.

Glad to hear things are working! It may take some routing changes in order for both wifi and 5g to work at the same time.

[Jerry Lin]

[Jerry Lin]

BTW, what are the routing changes suggested? Do I need to execute any commands? Or, do they happen automatically by some code or scripts?

[tom]

@Jerry-Lin Not something I can provide too much data on as I don't have a ton of linux network routing experience. But from what I understand you can use ip route to see how your network traffic is being routed for each network interface.

You can also change the default route via something like sudo ip route change default ..... (don't know the exact command format) might take some research.

[Jerry Lin]

OK, cool thanks

Will try.