Telit LE910C4-NF + T-Mobile

Hello,

We are trying to use the Sixfab kit with the LTE HAT and the Telit LE910C4-NF with a US T-Mobile SIM over ECM (because we are using Ubuntu 18.04 and the packages for running your script are only available on 20.04).

We following the instructions in Internet Connection with Telit LE910C1 module using ECM Mode and it seems to have set the APN properly and connected, but we don’t have an IP address on the wwan0 interface even though we brought it up with ifconfig. Below I have included some various commands I saw requested for debugging in another thread. Is there any way to determine what the the issue is? Is it lack of coverage (we have another T-Mobile SIM in an Android phone and it gets coverage in the same room)? Something still not configured quite right with the APN?

We also periodically seem to have trouble talking to the LTE module over minicom. It seems to get into a state where no keystrokes appear and minicom locks up until the USB cable is disconnected.

Also, is there an explanation of what the LEDs on the HAT mean? Sometimes the STAT light is solid blue, but most often is is blinking slowly at about 2Hz. Occasionally the USER LED is light green.

Regards,
Tom

AT+CPIN?                                                                        
+CPIN: READY                                                                    
                                                                                
OK                                                                              
AT+CREG?                                                                        
+CREG: 0,1                                                                      
                                                                                
OK                                                                              
AT+CGDCONT?                                                                     
+CGDCONT: 1,"IP","fast.t-mobile.com","",0,0,0,0                                 
+CGDCONT: 2,"IPV4V6","ims","",0,0,0,0                                           
+CGDCONT: 3,"IPV4V6","sos","",0,0,0,1                                           
+CGDCONT: 4,"IPV4V6","attm2mglobal","",0,0,0,0                                  
                                                                                
OK                                                                              
AT+CPIN??                                                                       
+CPIN: READY                                                                    
                                                                                
OK                                                                              
AT+QGMR                                                                         
ERROR                                                                           
AT+CPAS                                                                         
+CPAS: 0                                                                        
                                                                                
OK                                                                              
AT+CFUN?                                                                        
+CFUN: 1                                                                        
                                                                                
OK                                                                              
AT+COPS?                                                                        
+COPS: 0,0,"T-Mobile",7                                                         
                                                                                
OK                                                                              
AT+QCFG="band"                                                                  
ERROR                                                                           
AT+QCFG="nwscanseq"                                                             
ERROR                                                                           
AT+QCFG="iotopmode"                                                             
ERROR                                                                           
AT+CSQ                                                                          
+CSQ: 26,5                                                                      
                                                                                
OK                                                                              
AT+QCSQ                                                                         
ERROR                                                                           
AT+QNWINFO                                                                      
ERROR                                                                           
AT+CGATT?                                                                       
+CGATT: 1                                                                       
                                                                                
OK                                                                              
AT+QCFG="usbnet"                                                                
ERROR                                                                           
AT#ECM?                                                                         
#ECM: 0,1                                                                       
                                                                                
OK

Tom - any success? Are you using T-Mobile prepaid (Metro by T-Mobile) or postpaid?

Hi @john,
Nothing yet. We need to try to connect outdoors, just to rule out signal strength (another T-Mobile SIM works just fine in a Pixel phone at the same location) but that will require us to have a portable power source plus a monitor/keyboard for interacting with the Pi. We are using commercial lines from T-Mobile proper (postpaid).

thanks for the update - I’m curious how your project goes moving forward

i trying to figure out the same with a visible (vzwinternet) SIM card and it doesn’t work like it does with the Six fabs. I get IP connection on wwan0 but not able to ping or get a connection out. Does anybody know if these units only with with their sixfab sim cards… i thought this would be more"universal" because all the device is a radio and sim card reader, really… sixfabs please let us know so i know if i need to return the hat kit or what. i was planning on using this as a solution for internet hotspot, but not if i have to pay for overpriced sim card plan through six fabs.

Hi,

We can understand your concern to use Verizon SIM. From our past experience, most of our customers have failed to register their modules to the Verizon Network. As Sixfab we cannot claim that the modules will work with Verizon Network. To solve this chaos we have introduced Sixfab SIM cards.

Hi @ensar,

We aren’t using Verizon SIMs. It is T-Mobile US which is listed as being compatible on the product page for the Telit LE910C4-NF. Is there any troubleshooting suggestions you can provide? Is it a signal issue? Do we need to configure more than the APN?

Thanks,
Tom

Hey Sixfab, if you are doing any application with more intensive data use, the sixfab SIM plan at 10 cents per MB is several orders of magnitude higher cost per bit compared to a standard tmobile or att prepaid plan. (for example, Tmobile offers 30GB/Mo for $40)

This makes the sixfab/twilio cost prohibitive for some common tasks such as computer vision. it would be very nice to have a validated solution using a typical “hotspot” or other prepaid data-only plan in the U.S. market.

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It would be nice to compose a thread showing what SIM cards have worked and what the settings were that made them work okay. It would be even nicer if there was an online reference (periodically updated) showing exactly that.

We are aware of the high cost and we have introduced data pool plans to reduce costs. We have data pool plans for US(AT&T + T-Mobile). It is less costly than PAYG. See product page for data pool plans.

Hi Tom,

What is the AT#FWSWITCH setting? For T-Mobile it should be ‘2’.

Also, check your auto carrier switching function by SIM with AT#FWAUTOSIM.

source: LE910Cx AT Commands Reference Guide

To understand the network registration process and for troubleshooting, you may check the network registration application guide provided by the module OEM.

Thanks @ensar. We will take a look at the firmware switch setting and the registration guide.

Those data pool plans are still super expensive for any significant data usage when compared to plans offered by US carriers. :frowning: I hope someone comes up with a way to use a sim card with reasonable pricing.

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