Important update regarding LTE modem updates

robert-hh

@redferne See thes post of @Xykon below, which try to address this:
https://forum.pycom.io/topic/3549/important-update-regarding-lte-modem-updates/84
and
https://forum.pycom.io/topic/3549/important-update-regarding-lte-modem-updates/86

JoseDLopez

@stsiafak Thanks for you answer!

Did you make that test in Chile? If it so, wich operator? I am trying with telefonica/movistar

Finally i am trying with Huawei Node and after:
.
.
lte.send_at_cmd('AT+CFUN=1')
.
.
lte.send_at_cmd('AT+CGATT=1')

I receive:
error +CEREG: 4

It seems to be a problem with freq band selected. Can you guide me about what does that error mean?

Maybe? Error Code: 4 -> Operation not supported

Best regards,

tuftec

@xykon please advise when we can expect a response to the band 8 problem.
I was surprised to discover that this issue has been known about for 8 months now.
This is a critical stop point for our project. We have already eaten up precious time that we have arranged with Vodafone Australia for system trials.
Peter.

danielm

I performed successful tests in NB-IoT network of Slovak Telekom with Sequans FW NB1-38729 and Pycom FW 1.18.1.r2 provided by @Xykon .

As suggested by @peterv it was possible to reduce the code to:

lte = network.LTE()
lte.send_at_cmd('AT+CGDCONT=1,"IP","nbiot.telekom.sk"')
lte.attach(band=20)

Issues which remain unsolved from my point of view are:

working DNS over NB-IoT connection
support of PSM and eDRX

danielm

There is one more issue. Test application was sending MQTT message once per minute. After approx. 5 hours MQTT client returned exception [Errno 113] EHOSTUNREACH and each following attempt to reconnect to MQTT broker was unsuccessful.
The application also checks lte.isattached() and lte.isconnected() in each loop and if there is a change of state it prints out notification. There were no notifications therefore I assume that state of both lte.isattached() and lte.isconnected() remained True.

serafimsaudade

Hi,

I'm from Portugal, and I doing some testing the MEO NB network with 2 modems.
1 - Mangohred WP7702
2 - Pycom Gpy

I can connect with wp7702, and send data to our cloud server over UDP, MQTT. I also check the band use by the modem to connect, and is using the band 20.

With pycom, I try this code:

lte = network.LTE()
lte.send_at_cmd('AT+CGDCONT=1,"IP","internetm2m"')
lte.attach(band=20)
lte.isattached()

And the response is always False.
I update the sequans modem Firmware, but the result is the same.

I came to the conclusion that the sequans fw is not ready for the portuguese network. Or I'm doing something wrong?

cumps,
Luís Santos

robert-hh

@xykon Today I got the information that T-Mobile Germany uses band 8 for NBIoT (900 MHz band). So it would be useful to know, if this band is supported by the Sequans firmware is the attach is requested by the command AT!="RRC::addscanband band=8"
Trying to do that did not succeed even after 2 hours waiting.
At least, AT+CSQ tells me, that a cell is seen and a good signal can be received. But I have to go through a hard reset to get that.

tuftec

@robert-hh still wait on a response to band 8 support.
It appears that it is currently not supported.
This has put a halt to our developments at present.
Peter.

robert-hh

@tuftec What is your source of the missing band 8 support? Doers it tell that the Sequans firmware, or the Pycom firmware, not passing the request to the Sequans firmware.
If I compare the behavior between band 20 and band 8, it looks pretty similar. All commands are accepted, and then the Sequans modem is reporting alternating CEREG 2 and CEREG 0 on its TX line, only the period is different. For band 20, the period is 45 seconds, for band 8 it is 225 seconds.

tuftec

@robert-hh suggest you read the other posts in this thread. Particularly those from @Xykon.

It appears that the Sequans modem is not currently configured for band 8 support. A new firmware update is required.

Peter.

robert-hh

@tuftec I've read them all, and the conclusion is not obvious. Therefore I ask, if you have another source.

kevin

@robert-hh

@xykon said in Important update regarding LTE modem updates:

In regards to band 8, I was informed now that, while the hardware supports all bands (1,2,3,4,5,8,12,13,18,19,20,28), the Sequans firmware currently only supports a maximum of 6 bands so we chose the ones that gave us the best support at the time of launch. I have a call with Sequans later today to discuss this limitation and provide a firmware that can be used with band 8 as soon as possible. I hope to have an update on that within 24 hours.

The six bands that Pycom chose - i.e., the only ones currently supported by Sequans FW - are 3/4/12/13/20/28. We raised this issue about 8 months ago (https://forum.pycom.io/topic/2496/gpy-readiness/17), but still no progress.

dan

We are working on the additional bands with Sequans. We will post an update when we have more information. Thanks for your patience

Kurt Renauer

@dan thanx a lot for feedback, can't wait to see band=8 and isattached=true !

robert-hh

@kevin So this is what AT!="showCaps" returns:

== CAPS config =============================
  .Lock UE on SRV band    : false
  .MFBI support           : true
  .TM8 TDD support        : false
============================================
== CAPS ====================================
  . access stratum: R13
  . catM          : 1
  . nb-IoT        : 1
-- EUTRA bands --
  . supported     : 28/20/13/12/4/3
  . board         : 3/4/12/13/20/28
  . admin         : 
  . pending admin : 
-- EUTRA carriers --
  . admin         : 
  . pending admin : 
============================================

Definitely no support for band 8. Something like that would have been clear if shown right in the beginning.

tuftec

@dan please provide an indication as to when band 8 WILL be supported. It is nice to know that you are working on the problem but an expected release date would be greatly appreciated. Could you also please explain why direct emails to support@pycom.io and support team members go unanswered. This makes communication with the support team extremely difficult.

cnopicilin

@serafimsaudade said in Important update regarding LTE modem updates:

Hi,

I'm from Portugal, and I doing some testing the MEO NB network with 2 modems.
1 - Mangohred WP7702
2 - Pycom Gpy

I can connect with wp7702, and send data to our cloud server over UDP, MQTT. I also check the band use by the modem to connect, and is using the band 20.

With pycom, I try this code:
lte = network.LTE()
lte.send_at_cmd('AT+CGDCONT=1,"IP","internetm2m"')
lte.attach(band=20)
lte.isattached()
And the response is always False.
I update the sequans modem Firmware, but the result is the same.

I came to the conclusion that the sequans fw is not ready for the portuguese network. Or I'm doing something wrong?

cumps,
Luís Santos

The modem doesn't attach instantly, you should have the lte.isattached() in a loop like in the docs. Attaching can take minutes to complete.

while not lte.isattached():
    pass
print('Attached')

robert-hh

@serafimsaudade There is a problem with the lte.attach() command in parsing the response to the AT+CEREG? command, issued by lte.attach(). What do you get after the attach command with the coommands:

from network import LTE
lte.send_at_command('AT+CEREG?')

Attaching may take some time, like up to 15 Minutes.

EinarJ

Hi,

There is something wrong with the lte.isattached() in the 1.18.1.r1 (also in the latest beta-release).
When connecting a GPy to the Telenor NB-IoT network, we can verify the unit is attached, but the lte.isattached() gives 'False'
Running AT+CEREG and AT+CGATT also shows the device should be attached to the network:

lte.send_at_cmd('AT+CEREG?')
'\r\n+CEREG: 2,1,"9DD1","0105C06B",9\r\n\r\nOK\r\n'

lte.send_at_cmd('AT+CGATT?')
'\r\n+CGATT: 1\r\n\r\nOK\r\n'

lte.isattached()
False

Any suggestions?

robert-hh

@einarj @Xykon has made a trial firmware package addressign this bug. You can find it at [LINK NO LONGER AVAILABLE]
Download the matching package and install it using the path "Install from file".

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Important update regarding LTE modem updates

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