Telit 910C4-NF Modem Issues on Bell Network

Hello

I am trying to get a SixFab 3/4G.LTE Hat with a Telit 910C4-NF modem to connect with the Bell LTE network in Canada. The card and modem were used by a colleague of mine in the US on a different network, but I am not sure if it was with a SixFab SIM card or not, and he is gone now. I am using it with a BELL LTE SIM card and I have successfully used that same SIM card with a PiTalk Hat and a Quectel EG25 G modem so I am pretty confident in the SIM card.

I am following the guidelines at

(These same commands also work for the EG25 G modem on the PiTalk Hat)
All works fine on the SixFab HAT/Telit 910C4-NF modem until the line

sudo qmicli -p -d /dev/cdc-wdm0 --device-open-net=‘net-raw-ip|net-no-qos-header’ --wds-start-network= “apn=‘pda.bell.ca’, ip-type=4” --client-no-release-cid

This returns the error
error: couldn’t start network: QMI protocol error (14): ‘CallFailed’
call end reason (1018): gsm-wcdma-option-unsubscribed
verbose call end reason (6,33): [3gpp] option-unsubscribed
[/dev/cdc-wdm0] Client ID not released:
Service: ‘wds’
CID: ‘19’
There is no username or password required for the BELL SIM card.

The Telit modem seems to be requesting GSM-WCDMA service, but I know the network uses LTE in this area and the QUECETEL modem does connect with LTE radio interface.

It could also be that the Telit 910C4-NF modem is programmed for T-MOBILE, since the response to the command

sudo qmicli -d /dev/cdc-wdm0 --wds-get-profile-list=3gpp

seems to ignore any attempt to connect to pda.bell.ca

Profile list retrieved:
[1] 3gpp -
APN: ‘fast.t-mobile.com
PDP type: ‘ipv4’
PDP context number: ‘1’
Username: ‘’
Password: ‘’
Auth: ‘none’
No roaming: ‘no’
APN disabled: ‘no’
[2] 3gpp -
APN: ‘ims’
PDP type: ‘ipv4-or-ipv6’
PDP context number: ‘2’
Username: ‘’
Password: ‘’
Auth: ‘none’
No roaming: ‘no’
APN disabled: ‘no’
[3] 3gpp -
APN: ‘sos’
PDP type: ‘ipv4-or-ipv6’
PDP context number: ‘3’
Username: ‘’
Password: ‘’
Auth: ‘none’
No roaming: ‘no’
APN disabled: ‘no’
[4] 3gpp -
APN: ‘attm2mglobal’
PDP type: ‘ipv4-or-ipv6’
PDP context number: ‘4’
Username: ‘’
Password: ‘’
Auth: ‘none’
No roaming: ‘no’
APN disabled: ‘no’

Is there any reason the modem would be trying to connect in GSM/WCDMA mode? Any thoughts on how to debug what I think is a connection error using either AT or QMI commands would be greatly appreciated.

Thanks

Hi,

Use the command AT+CGDCONT? to check the existing PDP contexts and their APNs. Also, AT+CFUN=1,1 to reset the modem and then recheck the configuration.

Using the pda.bell.ca APN, you can run the following AT command: AT+CGDCONT=1,"IP","pda.bell.ca"

Force the modem to connect using LTE only with the following AT command: AT+WS46=28

To ensure your modem is successfully registered on the LTE network, use the following command: AT+CEREG?

To manually connect to Bell Canada’s LTE network, use: AT+COPS=1,2,"302610" # MCC/MNC for Bell Canada