CAT-M1 cannot Attached

[Terry666]

Device using: Gpy
SIM card: Hologram

I activated some hologram sim cards and test it on my Gpy but it cannot attach to the network. I test "at+cereg" in the loop of attaching, and the result is:

^EXIT: Assertion failed
+SYSSTART
+CEREG: 2,0

I tested Gpy that can work perfectly with the newly activated sim card, and it can connect.
But the same code on a new board with the same sim card, it cannot attach to the network. So I guess it is probably not the problem of sim cards.

My lte connection code is

lte.init()
lte.send_at_cmd('AT+CFUN=0')
lte.send_at_cmd('AT!="clearscanconfig"')
print("Hologram use"+lte.send_at_cmd('at+cgdcont=1,"IP","hologram"'))
lte.send_at_cmd('AT+CFUN=1')    
while not lte.isattached():
       time.sleep(0.5)
       attachTimeout += 1
       print(lte.send_at_cmd('AT+CEREG?')[:-1], end='')
       if attachTimeout == 15:
                print(" LTE Failed")
                time.sleep(0.750)
                #
                # Shutdown the LTE system
                if lte.isconnected:
                    lte.disconnect()
                    time.sleep(2)
                if lte.isattached():
                    lte.dettach()
                    time.sleep(2)
                lte.deinit(reset=True)
                machine.reset()
        print("lte is attached")

        ##
        # Now we busy wait for the Internet connection
        print("Start to connect")
        lte.connect()
        connectTimeout = 0
        while not lte.isconnected():
            time.sleep(1)
            connectTimeout += 1
            if connectTimeout == 15:
                # pycom.rgbled(ucot.LED_RED)
                time.sleep(0.750)
                # pycom.rgbled(ucot.LED_BLACK)
                print("lte is not connected")

                #
                # Shutdown the LTE system
                lte_off()
                
                # #
                # # Go to deepsleep for one tenth of a reporting interval
                # pySense.setup_sleep((REPORTING_INTERVAL/10) * 60)
                # pySense.go_to_sleep()
                machine.reset()
                time.sleep(1)
        print("lte is connected")

Is there any problem of this usage or do I need to specially config anything?

[robert-hh]

@Terry666 Can you try to set the timeout to a much larger value? For the first time, that may be needed.