Successful network connections?
I am scrolling through a lot of posts relating to difficulties in achieving a connection to LTE Cat-M1 networks. To encourage me to focus on my problem I am keen to know what networks/countries are currently connecting to the FiPy modules via CAT-M1. This will provide me with confidence in the module and encourage me to determine my path to a successful connection. Maybe a table of setups (Firmware, SIM source, Network provider, APN, CID, Antenna, Band, Expansion board/connection to module, etc) to assist others in achieving a connection in the same environment? Should I be able to find this in documentation?
Whoups ;-) Didn't realize that there was a complete overhaul on the Sequans support code. Anyway I changed to DL-EARFCN=1925 and got below result. It still does not register, in fact, there are no operators at all found:
>>> send_at_cmd_pretty('AT+CFUN?') +CFUN: 1 OK >>> send_at_cmd_pretty('AT+CPIN?') +CPIN: READY OK >>> send_at_cmd_pretty('AT+CEREG?') +CEREG: 4,4 OK >>> send_at_cmd_pretty('AT+COPS=?') +COPS: ,,(0,1,2,3,4),(0,1,2) OK >>> >>> send_at_cmd_pretty('AT!="fsm"') SYSTEM FSM ========== +--------------------------+--------------------+ | FSM | STATE | +--------------------------+--------------------+ | RRC TOP FSM |SCANNING | | RRC SEARCH FSM |WAIT_CELL_ID | | RRC ACTIVE FSM |NULL | | PMM PLMN FSM |NORM_WAITCELL | | EMM MAIN FSM |NULL | | EMM AUTH FSM |KASME_DEFINED | | EMM CONN FSM |NULL | | EMM TAU FSM |NULL | | EMM TEST FSM |NULL | | ESM BEARER FSM |BEARER_NULL | | SMS MT FSM |IDLE | | SMS MO FSM |IDLE | | HP MAIN FSM |IDLE | | HP USIM FSM |READY | | HP SMS MO FSM |IDLE | | HP SMS MT FSM |IDLE | | HP CAT FSM |IDLE | +--------------------------+--------------------+ OK >>> send_at_cmd_pretty('AT!="showphy"') DL SYNCHRO STATISTICS ===================== Synchro state : CELL SEARCH PPU SIB1 ACQ watchdog : 2 Frequency Hypothesis RF (Hz) : 0 RSRP (dBm) : -21474836.00 RSRQ (dB) : 0.00 Channel estimation state (Cell-spec.) : LOW CINR Channel estimation state (UE-spec.) : LOW CINR Channel estimation state (MBSFN) : LOW CINR Channel estimation CINR : 0.00 Channel length : SHORT AGC AGC RX gain (dB) : 48.31 RX PSD BO (dBFs) : -29.32 RX PSD (dBm) : -112.72 Noise level RS (dBm) : -128.24 Digital gain (dB) : 16.69 CINR RS (dB) : 0.00 NARROWBANDS Last DL NB : Central Last UL NB : 0 AFC Frequency offset RF (Hz) : 0 Frequency offset BB (Hz) : 0 PBCH MIB received quantity : 620 MIB timeout quantity : 0 OK
We expect EARFCN=1575 for band 3.
You can change it if you changes this line and build a custom firmware: https://github.com/pycom/pyupython/blob/master/esp32/mods/modlte.c#L313
Upgraded GPY to latest firmware, but still cannot get it to register on our inhouse Cat-M1 testnetwork on band 3 (EARFCN=1925). How can I check whether it even finds and tries to register on our network? AT+CEREG? returns 4, which means "unknown".
Some networks like Verizon do require certification, the devices just don't connect if the IMEI is not in the approved list. Most carrier support teams won't tell "home" users this, those details are only know by specific staff members.
There is also some confusion around what "certified" means. Some uncertified devices use modules which have been certified, have the module makers own IMEIs etc so they can connect.
The FiPy however custom built from a chip-on-board solution and using our own IMEIs so there different certification layers involved.
Good to know about APN "changeability". My discussions so far indicated that certification was not a requirement to get operational - but more to guarantee long term compatibility with the network provider, but I'm happy to be better informed.
Have also acquired SIMs that were said to be setup for use on CAT-M1 network, but not sure how that translates to use with the FiPy or Gpy as I assume the necessity to 'enable' the modem. Initially just looking to get a 'TRUE' condition for connection to a cell tower as a first step to an endorphin rush! Once that is achieved we can progress to unicorns and rainbows.
The FiPy is currently only certified with Verizon US so your experience with other carriers may vary.
Our latest firmware 1.17 is a huge step towards better support and since you can use AT commands you can also specify alternative APNs with:
We've also enabled scanning in more frequency bands.
We are building up more information and will have it up soon.