CATM1: CSQ and time to connect



  • All,
    On my Fipy unit ( with Hologram SIM ), it typically takes 25-60 seconds to connect( attach) to cell tower each time. This is a huge drain on my 4xD batteries that runs the unit. During this 25-60 seconds its fighting to connect to cell tower( goes through 10-20 retries ) and I get a CSQ of 99,99 and then between 7,99 17,99. After successful connect and transmit, I power-down the Fipy properly ( kill session, deattach etc) after to save power .
    I have been told it should take way less that 25-60 seconds ,so I replicated the same with other vendor modems and was able to connect and transmit in under 10 seconds.
    I am running the most recent firmware:

    >>> os.uname()(sysname='FiPy', nodename='FiPy', release='1.20.1.r1', version='v1.11-3138a13 on 2019-10-08', machine='FiPy with ESP32', lorawan='1.0.2', sigfox='1.0.1', pybytes='1.1.3')
    
    lte = LTE() 
    	#lte.attach(apn="hologram")    # attach the cellular modem to a base station, initially it was lte.attach()# add band 4 and 2
    	#time.sleep(5) # added 5 seconds wait
    	#pycom.rgbled(0xff0000) # RED LED
    	print('SIM ID#:%s'%lte.send_at_cmd('AT+SQNCCID'))
    	DeviceIMEI6=str(lte.send_at_cmd('AT+CGSN'))[11:17] # done if using IMEI last 6****
    	#needs to be an escape from this, will go on forever:
    	while not lte.isattached():
    		print('Signal:%s'%lte.send_at_cmd('AT+CSQ'))
    		print('Status:%s '%lte.send_at_cmd('AT+CEER'))
    		time.sleep(1)  # originally 0.25 changed to 5.0
    		lte.attach(apn='hologram') # add band 2, 4 ,13
    
    

    Example terminal out for the CSQ:

    Signal:
    +CSQ: 18,99
    OK
    Status:
    +CEER: lastEmmCause: NO CAUSE RECEIVED, lastEsmCause: NO CAUSE RECEIVED
    OK
    Signal:
    +CSQ: 18,99
    OK
    Status:
    +CEER: lastEmmCause: NO CAUSE RECEIVED, lastEsmCause: NO CAUSE RECEIVED
    Signal:
    +CSQ: 6,99
    OK
    Status:
    +CEER: lastEmmCause: NO CAUSE RECEIVED, lastEsmCause: NO CAUSE RECEIVED
    OK
    Signal:
    +CSQ: 7,99
    OK
    Status:
    +CEER: lastEmmCause: NO CAUSE RECEIVED, lastEsmCause: NO CAUSE RECEIVED
    OK
    

    I have repeated the same on multiple Fipy and Gpy using other SIM (verizon), different kinds of antenna, moved around to be closer to tower, but similar results.
    Thanks much in advance!!


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