MKR GSM 1400 - STUCK on AT+CREG?

Official Hardware MKR Family MKR GSM 1400
1

Hello everyone! I've read a lot of topics from this forum, but without result. I have SIM card in europe (czech) - vodafone. Im using example projects from MKRGSM.h library. Modem test passed! But if i try test GPRS im stuck on. No one example working where is intereseted in GSM thing. gsmAccess(true) on command:

AT+CREG?

07:57:09.938 -> +CREG: 0,0
07:57:09.938 -> 
07:57:09.938 -> OK

Arduino do it several times with same result and after it restart itself. Im using dipol antenna from ardino's store. I tried:

  1. change PIN from empty into "1234"
  2. external voltage between VIN and GND (5V / 2.1A) + USB for debug
  3. another antenna
  4. SIM works perfectly with phone / LTE router
  5. change band for all opinions
  6. tried same for NB 1500 chip

I have m-center application for testing u-blox chip and cannot get any info from AT terminal.

2

You can try:
Load serialGSMpasstrough sketch (under examples ->mkrgsm->tools)
Open Serial monitor
type ATI9 or AT in the serial command bar. then you should see a answer from the modem. If so, continue with the commands:
AT+CFUN=1
AT+IPR=921600
AT+UCALLSTAT=1
AT+CMGF=1
AT+UDCONF=1,1
AT+CTZU=1
AT+UDTMFD=1,2

and then

AT+CREG? until you see 0,1 or 0,5 in the answer. This can take minutes. See the uBlox AT manual.

PS:
-Remove PIN protection for the SIM to simplify testing purposes.
-The NB1500 modem can ONLY LTE-M or NB bands. It's not a full modem. If these bands are not supported in your area, nothing will work
-Check the AT command manual from u-blox for tests and debug

3

Thank you for reply!

Problem was with my GSM provider. They turn off GSM network in my location.