[Olimex BC66] - Random errors and no network attachment despite slow flashing NETLIGHT

brixton · January 12, 2022, 2:54pm

Hello,
I have an Olimex BC66. The NETLIGHT is flashing slowly with roughly 2 second intervals between the light blinks. According to the datasheet it means that the device is “connected” (whatever that means, assume that means CSON=1?)
However when I look at the CGATT, CSCON and CEREG commands it doesn’t seem like the device is connected. Furthermore, I am getting generic ERROR responses even though I selected AT+CMEE=1, meaning that I should be getting CME error codes. Very strange and very frustrating. If anyone would be able to help, that would be great. Many thanks.

I’m using this tutorial as a guideline. It’s suggesting to just wait for a connection…I have waited for more than an hour now.

[2022-01-12_15:45:50:024]ATE1

[2022-01-12_15:45:50:024]OK
[2022-01-12_15:45:51:917]ATi

[2022-01-12_15:45:51:917]Quectel_Ltd
[2022-01-12_15:45:51:917]Quectel_BC66
[2022-01-12_15:45:51:917]Revision: BC66NBR01A10

[2022-01-12_15:45:51:917]OK
[2022-01-12_15:45:53:797]AT+QCCID

[2022-01-12_15:45:53:797]+QCCID: 89882390000214136817

[2022-01-12_15:45:53:797]OK
[2022-01-12_15:45:56:699]AT+CPSMS=0

[2022-01-12_15:45:56:699]OK
[2022-01-12_15:45:57:712]AT+QSCLK=0

[2022-01-12_15:45:59:623]ERROR
[2022-01-12_15:46:08:242]AT+CEREG=5

[2022-01-12_15:46:08:242]OK
[2022-01-12_15:46:10:758]AT+CSON=1

[2022-01-12_15:46:10:758]ERROR
[2022-01-12_15:46:12:648]AT+QNBIOTEVENT=1,1

[2022-01-12_15:46:12:648]OK
[2022-01-12_15:46:15:011]AT+QBAND=1,20


[2022-01-12_15:46:15:027]OK
[2022-01-12_15:46:17:780]AT+QCGDEFCONT="IP","nb.inetd.gdsp"

[2022-01-12_15:46:17:780]OK
[2022-01-12_15:46:20:871]AT+CGPADDR?

[2022-01-12_15:46:20:871]OK
[2022-01-12_15:46:22:935]AT+SIDNSGIP=1,"www.gsma.com"

[2022-01-12_15:46:22:935]ERROR
[2022-01-12_15:46:25:361]AT+CESQ

[2022-01-12_15:46:25:361]+CESQ: 16,7,255,255,22,38

[2022-01-12_15:46:25:361]OK
[2022-01-12_15:46:27:311]AT+QENG=0

[2022-01-12_15:46:27:311]+QENG: 0,6254,3,408,"1883165",-102,-7,-95,5,20,"2FAC",0,230,2

[2022-01-12_15:46:27:311]OK
[2022-01-12_15:46:29:599]AT+CGATT?

[2022-01-12_15:46:29:599]+CGATT: 0

[2022-01-12_15:46:29:599]OK
[2022-01-12_15:46:34:469]AT+CSON? 

[2022-01-12_15:46:34:485]ERROR
[2022-01-12_15:46:40:003]AT+CSON? 

[2022-01-12_15:46:40:003]ERROR
[2022-01-12_15:46:56:312]AT+CEREG?

[2022-01-12_15:46:56:312]+CEREG: 5,2,,,,,0,0

[2022-01-12_15:46:56:312]OK
[2022-01-12_15:47:29:573]AT+SIDNSGIP=1,"www.gsma.com"

[2022-01-12_15:47:29:573]ERROR
[2022-01-12_15:49:58:025]AT+CMEE=1

[2022-01-12_15:49:58:025]OK
[2022-01-12_15:50:02:136]AT+SIDNSGIP=1,"www.gsma.com"

[2022-01-12_15:50:02:136]ERROR
[2022-01-12_15:50:07:156]AT+CGATT?

[2022-01-12_15:50:07:156]+CGATT: 0

[2022-01-12_15:50:07:156]OK
[2022-01-12_15:50:13:781]AT+CSON?

[2022-01-12_15:50:13:781]ERROR
[2022-01-12_15:50:15:244]AT+CSON?

[2022-01-12_15:50:15:244]ERROR
[2022-01-12_15:50:16:000]AT+CSON?

[2022-01-12_15:50:16:000]ERROR

brixton · January 12, 2022, 5:14pm

Update: I realise that I was typing CSCON wrong above in the commands . That’s now fixed and managed to set an Unsolicited Result Code for it. Now what I’m seeing is that the modem is continuously connecting and disconnecting… No idea what that means.

[2022-01-12_18:09:47:380]+CSCON: 1
[2022-01-12_18:09:58:438]
[2022-01-12_18:09:58:438]+CSCON: 0
[2022-01-12_18:09:58:573]
[2022-01-12_18:09:58:573]+CSCON: 1
[2022-01-12_18:10:09:685]
[2022-01-12_18:10:09:685]+CSCON: 0
[2022-01-12_18:10:10:093]
[2022-01-12_18:10:10:093]+CSCON: 1
[2022-01-12_18:10:21:428]
[2022-01-12_18:10:21:428]+CSCON: 0
[2022-01-12_18:10:21:610]
[2022-01-12_18:10:21:610]+CSCON: 1
[2022-01-12_18:10:32:634]
[2022-01-12_18:10:32:634]+CSCON: 0
[2022-01-12_18:10:32:815]
[2022-01-12_18:10:32:815]+CSCON: 1
[2022-01-12_18:10:43:932]
[2022-01-12_18:10:43:932]+CSCON: 0
[2022-01-12_18:10:44:326]
[2022-01-12_18:10:44:326]+CSCON: 1
[2022-01-12_18:10:55:454]
[2022-01-12_18:10:55:454]+CSCON: 0
[2022-01-12_18:10:55:860]
[2022-01-12_18:10:55:860]+CSCON: 1
[2022-01-12_18:11:07:245]
[2022-01-12_18:11:07:245]+CSCON: 0
[2022-01-12_18:11:07:368]
[2022-01-12_18:11:07:368]+CSCON: 1
[2022-01-12_18:11:16:504]    
[2022-01-12_18:11:18:416]+CSCON: 0
[2022-01-12_18:11:18:583]
[2022-01-12_18:11:18:583]+CSCON: 1
[2022-01-12_18:11:30:059]
[2022-01-12_18:11:30:059]+CSCON: 0
[2022-01-12_18:11:30:410]
[2022-01-12_18:11:30:410]+CSCON: 1
[2022-01-12_18:11:41:535]
[2022-01-12_18:11:41:535]+CSCON: 0
[2022-01-12_18:11:41:945]
[2022-01-12_18:11:41:945]+CSCON: 1
[2022-01-12_18:11:53:005]
[2022-01-12_18:11:53:005]+CSCON: 0
[2022-01-12_18:11:53:126]
[2022-01-12_18:11:53:126]+CSCON: 1
[2022-01-12_18:12:04:230]
[2022-01-12_18:12:04:230]+CSCON: 0
[2022-01-12_18:12:04:648]
[2022-01-12_18:12:04:648]+CSCON: 1

herbert.pan-Q · January 13, 2022, 1:55am

hi,Brixton:
This is normal, URC +cscon:1 means the network is connected, and since you’re not sending any data, you’re not interacting with the network, then the network will go to idle state URC +cscon:0; According to your log analysis, your local network remains connected for 10 seconds

brixton · January 13, 2022, 8:07am

Hi @herbert.pan-Q , thanks for that explanation.

But shouldn’t CEREG “stat” become 1 or 5 (registered) at some point? At the moment it’s continuously at “stat” = 2 (not registered).

Furthermore, why is CGATT constantly at “stat” = 0? That means that it’s not attached to the packet domain service. Shouldn’t CGATT have a value of “stat”=1 in order to be able to send data?

herbert.pan-Q · January 13, 2022, 10:23am

Oh, I understand, this terminal should have been rejected while attached to the network；t is inferred that it is mainly related to SIM cards. It is recommended that you try to replace other SIM cards

brixton · January 14, 2022, 4:25pm

Hi @herbert.pan-Q thank you for the suggestion. Yet I find that very hard to believe. When I use the exact same SIM card on a BC95-G module it does register to the EPS, and it does also attach to the Packet Domain Service. See logs.

On the BC66 however, the UE never seems to register/attach.

[2022-01-13_12:09:00:949]OK
[2022-01-13_12:09:12:842]AT+CEREG? 
[2022-01-13_12:09:12:842]+CEREG:5,2,0000,00000000,9,,,,

[2022-01-13_12:09:12:842]OK
[2022-01-13_12:10:36:959]AT+CEREG? 
[2022-01-13_12:10:36:959]+CEREG:5,2,0000,00000000,9,,,,

[2022-01-13_12:10:36:959]OK
[2022-01-13_12:11:11:589]
[2022-01-13_12:11:11:589]+CSCON:1
[2022-01-13_12:11:15:465]AT+CGATT? 
[2022-01-13_12:11:15:465]+CGATT:0

[2022-01-13_12:11:15:465]OK
[2022-01-13_12:11:21:514]AT+CGATT? 
[2022-01-13_12:11:21:514]+CGATT:0

[2022-01-13_12:11:21:514]OK
[2022-01-13_12:11:24:019]AT+COPS? 
[2022-01-13_12:11:24:019]+COPS:1,2,"20404"

[2022-01-13_12:11:24:019]OK
[2022-01-13_12:11:30:730]
[2022-01-13_12:11:30:730]+CEREG:5,2779,0191EB66,9,,,00000101,00101010
[2022-01-13_12:12:10:640]
[2022-01-13_12:12:10:640]+CSCON:0
[2022-01-13_12:12:12:669]
[2022-01-13_12:12:12:669]+CEREG:4,2779,0191EB66,9,,,00000101,00101010
[2022-01-13_12:16:33:015]AT+CSQ
[2022-01-13_12:16:33:015]+CSQ:99,99

[2022-01-13_12:16:33:015]OK
[2022-01-13_12:16:36:717]AT+CSQ
[2022-01-13_12:16:36:717]+CSQ:99,99

[2022-01-13_12:16:36:717]OK
[2022-01-13_12:16:40:810]AT+CSQ
[2022-01-13_12:16:40:810]+CSQ:99,99

[2022-01-13_12:16:40:810]OK
[2022-01-13_12:18:09:665]AT+CEREG? 
[2022-01-13_12:18:09:665]+CEREG:5,4,2779,0191EB66,9,,,00000101,00101010

[2022-01-13_12:18:09:665]OK
[2022-01-13_12:18:14:009]
[2022-01-13_12:18:14:009]+CEREG:5,2779,0191EB66,9,,,00000101,00101010
[2022-01-13_12:18:28:659]AT+CSQ
[2022-01-13_12:18:28:659]+CSQ:14,99

[2022-01-13_12:18:28:659]OK
[2022-01-13_12:18:29:043]
[2022-01-13_12:18:29:043]+CEREG:4,2779,0191EB66,9,,,00000101,00101010
[2022-01-13_12:18:32:442]AT+CSQ
[2022-01-13_12:18:32:442]+CSQ:99,99

[2022-01-13_12:18:32:442]OK
[2022-01-13_12:18:35:856]AT+CGATT? 
[2022-01-13_12:18:35:871]+CGATT:1
[2022-01-13_12:18:35:886]
[2022-01-13_12:18:35:886]OK
[2022-01-13_12:18:57:086]AT+CSCON? 
[2022-01-13_12:18:57:086]+CSCON:1,0

[2022-01-13_12:18:57:086]OK
[2022-01-13_12:19:08:346]AT+CEREG? 
[2022-01-13_12:19:08:362]+CEREG:5,4,2779,0191EB66,9,,,00000101,00101010

[2022-01-13_12:19:08:438]OK
[2022-01-13_12:19:09:712]
[2022-01-13_12:19:09:712]+CEREG:5,2779,0191EB66,9,,,00000101,00101010
[2022-01-13_12:19:58:755]AT+CSQ
[2022-01-13_12:19:58:770]+CSQ:12,99

[2022-01-13_12:19:58:786]OK
[2022-01-13_12:20:09:826]AT+CSCON? 
[2022-01-13_12:20:09:826]+CSCON:1,0

[2022-01-13_12:20:09:826]OK
[2022-01-13_12:20:16:338]AT+CGATT? 
[2022-01-13_12:20:16:338]+CGATT:1

[2022-01-13_12:20:16:338]OK
[2022-01-13_12:20:25:510]

herbert.pan-Q · January 15, 2022, 1:25am

hi,Brixton:
This common problem also exists in China, mainly due to terminal and card binding；
Therefore, I suggest the following:

Replace the NEW SIM card and debug the BC66;
Check with the SIM card provider or radio network operator to see if there is a terminal binding;
You can capture logs to analyze possible causes of network registration failure.

brixton · January 17, 2022, 10:42am

HI @herbert.pan-Q ,

when I use a NEW SIM card for the BC66, I get a CEREG message saying that ‘registration is denied’. See below. I’ve never seen a message like that before.
I have asked my SIM card provider about the SIM problem.
I have tried to capture logs by attaching a serial connection to the debug port of the BC66, and using QCOM software (1.6 version). However the output I get is scrambled. Any idea what could be going wrong here? I have seen “genie log” been recommended here and here as a debug tool, but I have no idea how to use that or where to get it from.

[2022-01-17_11:12:30:921]RRRRRó
[2022-01-17_11:12:31:151]+CPIN: READY
[2022-01-17_11:12:36:934]ATE1

[2022-01-17_11:12:36:934]OK
[2022-01-17_11:12:42:067]ATi

[2022-01-17_11:12:42:067]Quectel_Ltd
[2022-01-17_11:12:42:067]Quectel_BC66
[2022-01-17_11:12:42:067]Revision: BC66NBR01A10

[2022-01-17_11:12:42:067]OK
[2022-01-17_11:12:44:468]AT+CMEE=1

[2022-01-17_11:12:44:468]OK
[2022-01-17_11:12:47:104]AT+QSCLK=0

[2022-01-17_11:12:47:104]OK
[2022-01-17_11:12:48:146]AT+CIMI

[2022-01-17_11:12:48:146]901405340011497

[2022-01-17_11:12:48:146]OK
[2022-01-17_11:12:49:851]AT+CGMI

[2022-01-17_11:12:49:851]Quectel_Ltd
[2022-01-17_11:12:49:851]Quectel_BC66
[2022-01-17_11:12:49:851]Revision: MTK_2625

[2022-01-17_11:12:49:851]OK
[2022-01-17_11:12:51:100]AT+CGSN=1

[2022-01-17_11:12:51:100]+CGSN: 867997032558396

[2022-01-17_11:12:51:100]OK
[2022-01-17_11:12:54:120]AT+QBAND=1,8


[2022-01-17_11:12:54:120]OK
[2022-01-17_11:12:59:705]AT+QCGDEFCONT="IP","cdp.iot.t-mobile.nl"

[2022-01-17_11:12:59:705]OK
[2022-01-17_11:13:01:609]AT+COPS=1,2,"20416"
[2022-01-17_11:13:21:335]AT+QRST=1

[2022-01-17_11:13:21:335]+CME ERúRRRRRRóAT+QSCLK=0

[2022-01-17_11:13:27:374]OK
[2022-01-17_11:13:33:054]AT+CPSMS=0

[2022-01-17_11:13:33:054]OK
[2022-01-17_11:13:35:686]AT+CEREG=5

[2022-01-17_11:13:35:686]OK
[2022-01-17_11:13:40:757]AT+CEREG?

[2022-01-17_11:13:40:757]+CEREG: 5,3,,,,,0,19

[2022-01-17_11:13:40:757]OK
[2022-01-17_11:13:49:079]AT+CSQ

[2022-01-17_11:13:49:079]+CSQ: 11,0

[2022-01-17_11:13:49:079]OK
[2022-01-17_11:13:52:730]AT+CGATT=1

[2022-01-17_11:13:52:730]ERROR
[2022-01-17_11:13:56:912]AT+CGATT?

[2022-01-17_11:13:56:912]+CGATT: 0

[2022-01-17_11:13:56:912]OK
[2022-01-17_11:14:24:866]AT+CSCON?

[2022-01-17_11:14:24:866]+CSCON: 0,0

[2022-01-17_11:14:24:866]OK

WizIO · January 17, 2022, 10:54am

try ( for test ) with external antena

brixton · January 17, 2022, 10:59am

Hi @WizIO , you’re suggesting that I attach an external antenna to the board? Currently I’m using this Olimex BC66 development board, which already has an external antenna attached to it. So there’s not much I can change there unfortunately.

WizIO · January 17, 2022, 11:21am

yep … external antenna … just for test

brixton · January 17, 2022, 2:36pm

One part of the problem has been resolved!
The reason that the BC66 was not connecting whilst the T-Mobile SIM card was inserted, is because I got the APN wrong. I was following this T-Mobile BC66 tutorial, but the APN that was mentioned there is only applicable if you’re using a T-Mobile SIM card that is part of a “IoT creators project”. If you’re using a regular “T Mobile Easy Connnect” IoT SIM card, then the APN is just “iot.t-mobile.nl”. I changed the APN, and now the UE does attach to the network which is great!

So that means that the Olimex module works fine with the T-Mobile SIM.

The problem with the vodafone SIM card is not resolved however. I will try to get my hands on a new vodafone SIM card, to see if SIM card terminal binding is the issue.

brixton · January 19, 2022, 12:45pm

For the Vodafone SIM card the problem has now been resolved as well! It looks like terminal binding / IMEI lock was the problem, because with a new SIM everything went well. .