CELLULAR IOT HAT Connetion Unstable

ray · February 22, 2020, 3:33am

Hi,

For a while I managed to see my IOT HAT getting ip.Using QMI interface. So I left it over night and when I check next morning no internet was there. After that I rebooted and since then I get a loop of
requestRegistrationStat2 MMC:0, MNC: 0 , PS: Detached, DataCap : Unknown.
requestRegistrationStat2 MMC:311, MNC: 480 , PS: Detached, DataCap : Unknown

I have tried with 2 HATs in 2 different pi and both have same issue. I was really happy when I saw it work now Im frustrated as I have bought 2 HAT and planned to buy many more but can not get reliable behavior from this shield. Any help is appreciated.

saeed · February 26, 2020, 12:09pm

Hello Ray,

Which ISP and RAT are you using?

Share the output of the follwing AT commands.
AT+QCFG=“band”
AT+QCFG=“nwscanseq”
AT+QCFG=“nwscanmode”
AT+QCFG=“iotopmode”
AT+CSQ
AT+QCSQ
AT+CGREG?
AT+COPS?
AT+CGATT?

frank.lombardo · October 20, 2020, 1:42pm

I have the same problem and these commands say not found when I run them

ensar · October 20, 2020, 1:48pm

Hi @frank.lombardo,

Please follow the following tutorial to send AT commands:

frank.lombardo · October 20, 2020, 3:45pm

AT+QCFG=“band”
+QCFG: “band”,0x260,0x80a,0x0

OK
AT+QCFG=“nwscanseq”
+QCFG: “nwscanseq”,0403010502

OK
AT+QCFG=“nwscanmode”
+QCFG: “nwscanmode”,0

OK
AT+QCFG=“iotopmode”
ERROR
AT+CSQ
+CSQ: 22,99

OK
AT+QCSQ
+QCSQ: “LTE”,69,-98,113,-11

OK
AT+CGREG?
+CGREG: 0,5

OK
AT+COPS?
+COPS: 0,0,“AT&T Twilio”,7

OK
AT+CGATT?
+CGATT: 1

OK

frank.lombardo · October 20, 2020, 3:49pm

I can reconnect but connection fails overnight everytime I try

frank.lombardo · October 20, 2020, 8:41pm

Any ideas why my connection fails over night and I must restart to reconnect

ensar · October 21, 2020, 10:39pm

Hİ @frank.lombardo,

Add “persist” to /etc/ppp/peers/provider file. The persist option will keep pppd alive in case of a disconnect or when it can’t connect in the first place.

https://tldp.org/HOWTO/Leased-Line/pppd.html

frank.lombardo · October 22, 2020, 1:36pm

requestRegistrationState2 err = 110
QmiThreadSendQMITimeout pthread_cond_timeout_np timeout

are the errors displayed when I get status of service

frank.lombardo · October 22, 2020, 2:00pm

I am using Using QMI interface not PPP

ensar · October 27, 2020, 2:59pm

We recommend that you set up PPP connection for a stable connection.

frank.lombardo · October 27, 2020, 3:32pm

IQMI was used as it is the recomendation in your guide:

ensar · October 27, 2020, 3:47pm

Since this topic is in the “Cellular IoT HAT” category, I thought you were using Cellular IoT HAT.

frank.lombardo · October 27, 2020, 6:19pm

Thank you seems I was using wrong guide for my device