XBEE 3 Cell LTEM/NBIoT PPP Chat Script Issues

XBee & XBee Gateway
1

Following this guide:
https://www.digi.com/resources/documentation/Digidocs/90002258/tasks/t_ppp_lte-m_nbiot.htm?TocPath=Modes|USB%20direct%20mode|_____3

On ubuntu 20.04, the supplied chat script fails with time outs on various lines. Most time it won’t get past sending and waiting for the “AT” response. When I enter the commands via minicom connecting to /dev/ppp_direct_usb, I get the expected responses.

My initial thought is that it is missing the response from the modem. I have tried various matches in the chat script, but nothing is working consistently. Over 2 days of trying to get the modem up, I have only been successful 1 time.

Has anyone had this issue before?

2

As long as you are using the USB Direct pins and have the radio in USB direct mode, it should work.

3

Yeah, “should”. Any other insights?

4

XCTU should allow you to discover the USB ports that are installed. It should also allow you to determine which USB port is the main port for the U-Blox component.

5

Ok; So I have been able to get the modem to dial out and connect to the network. Problem is the modem hangs in data mode because the network is hanging up after authentication, which is odd since I have the noauth option set. I created another post for that problem since it is not related to this issue.

6

Actually, they are probably related. Check with your carrier to make sure that:

1: The SIM account is active
2: That it does not require a user name/password sent to auth. on the network
3: You have the correct APN for your account