如何使用 PyCom FiPy 连接到 LTE 蜂窝网络？

我正在尝试让 PyC​​om FiPy 板与 LTE 网络连接一起工作。我有一张全息 SIM 卡。我正在使用两段代码。一个来自 PyCom文档，另一个来自我在 PyCom 论坛上找到的用于调试LTE 的代码。

PyCom LTE Docs 中的第一个代码片段

import time
from network import LTE

print('main-testy.py starting.  This is the code snippet from pycom docs')

#lte = LTE(carrier="verizon")
lte = LTE()


print("trying to attach")
lte.attach(band=13)
while not lte.isattached():
    time.sleep(0.5)
    print('Attaching...')

print("trying to connect")
lte.connect(cid=3)
while not lte.isconnected():
    time.sleep(0.5)
    print('Connecting...')

# Now use sockets as usual...

输出

最初几次我运行这段代码时，它会附加，然后在lte.connect调用时生成一个 python 错误。原始样本使用“verizon”的载体，但论坛帖子说没有必要。

>>> Running main-testy.py

>>> 
>>> 
main-testy.py starting.  This is the code snippet from pycom docs
trying to attach
Attaching...
Attaching...
Attaching...
.. never attaches

来自 PyCom LTE 论坛帖子的第二个代码片段

浏览论坛，我发现其他一些用户也有类似的问题。我将他们的尝试与文档中的一些可用命令结合起来编写此代码。它提供了一些有关 SIM 卡和调制解调器的基本信息。这是那个代码。

# Determine carrier notes
from network import LTE


# 1817



lte = LTE()

def send_at_cmd_pretty(cmd):
    response = lte.send_at_cmd(cmd).split('\r\n')
    for line in response:
        print(line)


print("get phy status")
send_at_cmd_pretty('AT!="showphy"')     # get the PHY status
print("get System FSM")
send_at_cmd_pretty('AT!="fsm"')         # get the System FSM
print("get System COPS.  PLMN Selection: +COPS")
print("!!!!!!!!!1 always generates error !!!!!!!!!!!!")
send_at_cmd_pretty('AT+COPS=?')         # get the System FSM


print("get conformance test modes. List of carriers? ")
send_at_cmd_pretty("AT+SQNCTM=?")       # get list of carriers for
# results are
# "3gpp-conformance", "att", "docomo", "kt", "lgu", "softbank", "standard", "telstra", "verizon")

results = lte.imei()
print("lte.imei results \n{}" . format(results))


results = lte.iccid()
print("lte.iccid results \n{}" . format(results))

输出

所有这些代码都运行，但其中一个命令 (+COPS) 出现错误。我确实检查了 AT 命令参考，语法是 +COPYS=? 看起来是正确的。也许该特定命令只能在附加后才能发出。

>> Running lte-basic-operations.py

>>> 
>>> 
get phy status

DL SYNCHRO STATISTICS
=====================
    Synchro state                         : OFF
    PPU SIB1 ACQ watchdog                 : 0
    Frequency Hypothesis RF  (Hz)         : 0
    RSRP (dBm)                            : 0.00
    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)                      : 0.00
    RX PSD BO (dBFs)                      : 0.00
    RX PSD (dBm)                          : 0.00
    Noise level RS (dBm)                  : 0.00
    Digital gain (dB)                     : 0.00
    CINR RS (dB)                          : 0.00
  NARROWBANDS
    Last DL NB                            : 0
    Last UL NB                            : 0
  AFC
    Frequency offset RF  (Hz)             : 0
    Frequency offset BB  (Hz)             : 0
  PBCH
    MIB received quantity                 : 0
    MIB timeout quantity                  : 0

OK

get System FSM

SYSTEM FSM
==========
    +--------------------------+--------------------+
    |            FSM           |        STATE       |
    +--------------------------+--------------------+
    | RRC TOP FSM              |STOPPED             |
    | RRC SEARCH FSM           |NULL                |
    | RRC ACTIVE FSM           |NULL                |
    | PMM PLMN FSM             |NULL                |
    | EMM MAIN FSM             |NULL                |
    | EMM AUTH FSM             |NULL                |
    | 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              |NULL                |
    | HP SMS MO FSM            |IDLE                |
    | HP SMS MT FSM            |IDLE                |
    | HP CAT FSM               |NULL                |
    +--------------------------+--------------------+

OK

get System COPS.  PLMN Selection: +COPS
!!!!!!!!!1 always generates error !!!!!!!!!!!!

ERROR

get conformance test modes. List of carriers? 

+SQNCTM: ("3gpp-conformance", "att", "docomo", "kt", "lgu", "softbank", "standard", "telstra", "verizon")

OK

lte.imei results 
354346095554902
lte.iccid results 
8944500208186565235
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