nb-iot on t-mobile in NL



  • Re: nb-iot on t-mobile NL

    as for how far we are now this should be possible.

    i have send my fipy's back and i should have band 8 support now.
    is there anyone with an example on how to connect here.

    So far i can't do a succesfull attach to the network but maybe there are other settings needed than stated in the nb-iot connect example



  • @eric-waai These settings should be fine then.



  • @robert-hh
    hmm i can try that settings
    i used this settings
    Frequency Range: Guard Band
    Radio band: band 8, 900 Mhz
    APN: cdp.iot.t-mobile.nl
    PLMN ID: 20416
    NCDP address for Neul Messaging (CoAP): 172.27.131.100 Port 5683
    CDP address for UDP messaging: 172.27.131.100 Port 15683
    Hostname for using the API: https://iot.netwerk.t-mobile.nl
    Supported TLS certifications: TLS v1.1 and TLS v 1.2

    as described here
    https://docs.iot.t-mobile.nl/docs/general-settings



  • @eric-waai b.t.w.: which apn have you specified?
    I found a link where some of that is discussed: https://forum.iot.t-mobile.nl/topic/25/nieuwe-settings-voor-nb-iot-hardware-en-api/11



  • @robert-hh
    still not getting anywhere

    this is the result of showpy

    DL SYNCHRO STATISTICS

    =====================
    Synchro state : DRX_SLEEP
    PPU SIB1 ACQ watchdog : 0
    Frequency Hypothesis RF (Hz) : 0
    RSRP (dBm) : -82.24
    RSRQ (dB) : -12.62
    Channel estimation state (Cell-spec.) : LOW CINR
    Channel estimation state (UE-spec.) : LOW CINR
    Channel estimation state (MBSFN) : LOW CINR
    Channel estimation CINR : 5.23
    Channel length : SHORT
    AGC
    AGC RX gain (dB) : 42.57
    RX PSD BO (dBFs) : -18.79
    RX PSD (dBm) : -83.06
    Noise level RS (dBm) : -87.31
    Digital gain (dB) : 3.90
    CINR RS (dB) : 5.07
    NARROWBANDS
    Last DL NB : Central
    Last UL NB : 0
    AFC
    Frequency offset RF (Hz) : -447
    Frequency offset BB (Hz) : 0
    PBCH
    MIB received quantity : 0
    MIB timeout quantity : 0

    if i send AT+COPS=1,2,"20416" (tmobile specific)

    i get
    +CEREG: 2

    +CREG: 2

    OK

    +CGATT: 0

    OK

    +CEREG: 1,2

    OK

    +CFUN: 1

    OK

    OK

    OK

    +CGATT: 0

    OK

    +CEREG: 1,2

    OK

    +CFUN: 1

    OK

    OK

    as return

    if i later again send AT+C(E)REG
    i get +CREG: 1,0
    lte.isattached() is still false

    but the statistics change

    DL SYNCHRO STATISTICS

    =====================
    Synchro state : CELL_ACQUIRED
    PPU SIB1 ACQ watchdog : 0
    Frequency Hypothesis RF (Hz) : 0
    RSRP (dBm) : -82.88
    RSRQ (dB) : -11.70
    Channel estimation state (Cell-spec.) : HIGH CINR
    Channel estimation state (UE-spec.) : LOW CINR
    Channel estimation state (MBSFN) : LOW CINR
    Channel estimation CINR : 6.45
    Channel length : SHORT
    AGC
    AGC RX gain (dB) : 42.49
    RX PSD BO (dBFs) : -20.98
    RX PSD (dBm) : -84.72
    Noise level RS (dBm) : -89.38
    Digital gain (dB) : 5.66
    CINR RS (dB) : 6.50
    NARROWBANDS
    Last DL NB : Central
    Last UL NB : 0
    AFC
    Frequency offset RF (Hz) : -452
    Frequency offset BB (Hz) : 0
    PBCH
    MIB received quantity : 0
    MIB timeout quantity : 0



  • @eric-waai As far as I understand it, the coding for CREG and CEREG is the same. The 0 means: not registered, not searching.
    At my set-up, while waiting for attach, the result of AT+CEREG? is 2,2 most of the time and rarely 2,0



  • according http://m2msupport.net/m2msupport/atcreg-network-registration/
    CREG 1,0
    means registered, home network
    on GSM
    i assumed that for CEREG it meant somewhat the same
    will try again tomorrow



  • @eric-waai CEREG1,0 means:
    enable network registration unsolicited result code (1) and
    not registered, MT is not currently searching an operator to register to (0)
    You should see something like CEREG 2,0 or CEREG 2,2 while searching.
    AT+CSQ result is good. It means, the device detects a strong signal.

    I'm testing with v1.20.0.rc3



  • @robert-hh
    AT+CSQ is usually around 23-25,99

    CREG gives (1,0)
    and CEREG also (1,0)

    which would indicate it is somewhat connected

    but CGATT gives 0



  • @eric-waai i 1hour is too long.
    what is the result of lte.send_at_command('At+CSQ') while waitung for is_attached()



  • yes modem software is NB1-40343
    esp32 firmware is the last stable release 1.18.1.r7

    for now i waited over 1 hour without attach



  • @eric-waai Did you update both the sequans firmware and the ESP32 firmware to the most recent version ?
    And also, the first attach may take very long time, like 20 minutes.



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