Troubleshoot GPy connect to NB-IoT
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Hi,
Would like to seek advise on how to troubleshoot connecting GPy to NB-IoT network.
All firmware upgraded to the latest, and tested together with operator (Ericsson & use in-band), it seems cannot attach to the network, wonder if there is any AT command / suggested way to see whats wrong with it.
What I have tried so far in terminal:
from network import LTE
lte = LTE()
lte.send_at_cmd('AT+CFUN=0')
'\r\nOK\r\n'
lte.send_at_cmd('AT!="clearscanconfig"')
'\r\n\r\nOK\r\n'
lte.send_at_cmd('AT!="addscanfreq band=8 dl-earfcn=3741"')
'\r\n\r\nOK\r\n'
lte.send_at_cmd('AT!="zsp0:npc 1"')
'\r\n\r\nOK\r\n'
lte.send_at_cmd('AT+CGDCONT=1, "IP", "iotest"')
'\r\nOK\r\n'
lte.send_at_cmd('AT+CFUN=1')
'\r\nOK\r\n'
print (lte.isattached())
Falselte.send_at_cmd('AT+CEREG?')
'\r\n+CEREG: 2,4\r\n\r\nOK\r\n'
lte.send_at_cmd('AT+COPS=?')
''
By the way, what does lte.send_at_cmd('AT!="zsp0:npc 1"') do?Cheers,
Vincent
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@vli
did you find a way to enable scrambling?
having the same problem here
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Hi All,
Simply if there is a way to enable NB-IoT Scambling Feature.
Cheers
vli
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Hi @jmarcelino
Tried by giving sufficient time after CFUN=1, still gives CEREG: 2,4.
Further discussed with their Engineer, they had similar experience (unable to attach) with other vendor's product and is wondering if the current radio firmware on GPy do comply/implemented with the Change Request specified in the 3GPP TS 36.211 as highlighted in the following table.
Regards,
Vincent
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Hi @jmarcelino
The EARFCN in use for LTE is 3750, the in-band EARFCN for NB-IoT is 3741 - thats the one reported from another working EVB from other chipset maker. I tried both but with no luck.
I will try again with longer wait time before checking if is attached.
Thx!
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Hi @vli
I take it that your dl-earfcn=3741 is correct for the network you're using?
Have you given sufficient time after CFUN=1 (30+ seconds)?
The "zsp0:npc 1" are internal Sequans commands unfortunately there's no public information on those we can share.
