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AT&T IoT Starter Kit - Cellular Shield not attaching to APN - SIM OK, Settings OK?

Cellular Shield not attaching to APN - SIM OK, Settings OK?
05.28.2017 11:08 AM
Have the shield connected to a RPi3. Registered and activated the SIM, ICCID matches from device and in Control Center. But it fails the network connect test

Green LED on the shield. Both Antennas are connected and secured tightly.

Configured the APN properly:

AT
OK

AT%PDNSET?

%PDNSET: 1,m2m.com.attz,IP,,,,,0

SIM is ready:
AT+CPIN?
 
+CPIN: READY

AT%STATUS="USIM"

USIM: REAL USIM, LTE, Activated 1 times, Verified 1 times

AT%STATUS="UICC"

UICC: 5
 
 
Firmware is latest:
ATI

Manufacturer: WNC
Model: M14A2A
Revision: MPSS: M14A2A_v11.50.164451 APSS: M14A2A_v11.53.164451
 

It is in Full Functionality mode:
AT+CFUN?
+CFUN: 1

The device is not attached:
AT%CMATT?
%CMATT: 0
 
And, I have no signal it seems. I have tried various areas and spot, and my other ATT devices have signal fine.
AT+CSQ
+CSQ: 99,99


I do get an eth1 device, but it keeps providing a 10.0.0.x IP address so I am not getting onto the network. 


Also, it keeps disconnecting/connecting. (I see this over and over in the logs):

[  622.037476] usb 1-1.2: new high-speed USB device number 5 using dwc_otg
[  622.168549] usb 1-1.2: New USB device found, idVendor=1435, idProduct=3142
[  622.168563] usb 1-1.2: New USB device strings: Mfr=13, Product=14, SerialNumber=15
[  622.168572] usb 1-1.2: Product: 'WNC M14A2A devboard'
[  622.168580] usb 1-1.2: Manufacturer: 'WNC'
[  622.168587] usb 1-1.2: SerialNumber: usb_serial_num_0
[  622.171890] cdc_ether 1-1.2:1.0 eth1: register 'cdc_ether' at usb-3f980000.usb-1.2, CDC Ethernet Device, 00:11:22:33:44:56
[  622.175019] cdc_acm 1-1.2:1.2: ttyACM1: USB ACM device
[  622.185250] cdc_acm 1-1.2:1.4: ttyACM2: USB ACM device
[  622.191853] cdc_acm 1-1.2:1.6: ttyACM3: USB ACM device
[  622.342960] cdc_ether 1-1.2:1.0 eth1: kevent 12 may have been dropped
[  622.343204] IPv6: ADDRCONF(NETDEV_UP): eth1: link is not ready
[  624.391341] IPv6: ADDRCONF(NETDEV_CHANGE): eth1: link becomes ready

I am at a loss of where to go to debug this from here? Any ideas?
 
Re: Cellular Shield not attaching to APN - SIM OK, Settings OK?
05.28.2017 11:29 AM
One other thing. Here is Registration status which indicates it is trying to connect/find an operator:

AT+CREG?
+CREG: 2,2
 
Re: Cellular Shield not attaching to APN - SIM OK, Settings OK?
06.07.2017 10:00 PM
Anyone got any ideas of where to keep debugging? I am at a loss and there doesn't seem to be any support from AT&T for the starter kit as no one has responded to me.
Re: Cellular Shield not attaching to APN - SIM OK, Settings OK?
06.08.2017 12:46 PM
Michael,
Can you confirm if you are using the power supply that came with the shield?
That 5V supply outputs 2.4A which is needed to ensure consistent TX/RX performance with the cellular network.
If the unit is just drawing from the RPi or a regular 1.0A tyope of output there will be enough power for it to operate but not enough for it to perform correctly.
The troubleshooting you have done indicates the unit is operational and the service is provisioned correctly.
The power supply would be the first thing I would check.
Re: Cellular Shield not attaching to APN - SIM OK, Settings OK?
06.08.2017 01:17 PM
I had it getting power from the RPi USB ports, let me try direct power.
Re: Cellular Shield not attaching to APN - SIM OK, Settings OK?
06.08.2017 02:50 PM
Using the 2.4A shield power supply I have same issues.
Re: Cellular Shield not attaching to APN - SIM OK, Settings OK?
09.05.2017 09:51 AM
Has there been any resolution to this problem? I am experiencing the same sympotms with a shield connected directly to a terminal and AT commands issues manually. The shield is connected to the provided power supply. 
Re: Cellular Shield not attaching to APN - SIM OK, Settings OK?
09.05.2017 01:00 PM
Sadly no. I was contacted by support staff but after a couple emails back and forth I was not able to get access to any support people that could help so I basically scrapped the device and decided to go with a different approach. I would prefer to have this shield working though :(
Re: Cellular Shield not attaching to APN - SIM OK, Settings OK?
09.05.2017 01:14 PM
Thanks for the follow-up! I will be sure to post here if I make any progress.
Re: Cellular Shield not attaching to APN - SIM OK, Settings OK?
09.06.2017 01:17 PM
I ran into similar problem and this is what I had to do:
  1. disable (or at least stop) NetworkManager. It does not seem to work properly with StarterKit eth port
  2. bring interface up manually: ifconfig eth1 up
  3. the interface does not get the IP address from the shield, you have to use AT command in the serial terminal (minicom or similar) to find the proper IP address: AT+GCPADDR
  4. take that IP and configure the inteface with it: ifconfig eth1 <your IP address>/32. Make sure to use single host netmask (/32)
  5. add eth1 as a default route: route add default eth1
That fixed the problem for me, but your mileage may vary.
Re: Cellular Shield not attaching to APN - SIM OK, Settings OK?
09.06.2017 07:23 PM
Misspelled the command in #3, it's AT+CGPADDR.