Thingy91: Wait until connected

Question

Hi, 
 I am using the Thingy 91 and I have a program, where I first read GPS, then switch to NBIoT Mode and then send the data to a server. 
 However if I switch the Antenna to NBIoT Mode, I have to wait a certain amount of time until the Thingy 91 has connected to a NB-IoT tower. Otherwise there is an error and the program stops working. So I let the Thingy91 wait for 30 seconds and then it has hopefully connected, otherwise there is an error. 
 Is there an option to check if the Thingy91 has already connected to the NB-IoT Tower/the Internet? 
 Because then the program would be much more reliable and faster. 
 
 Thanks for your help and answers!

Jan Tore Guggedal · Accepted Answer

Hi, 
 Adding a bit to Heidi's answer, if you want to use a higher level of abstraction in your application. 
 nRF Connect SDK offers a convenience library for LTE link control: https://github.com/NordicPlayground/fw-nrfconnect-nrf/blob/master/include/lte_lc.h 
 It offers, among other things, APIs to set modem's system mode and connect/disconnect to LTE network. To enable it, set CONFIG_LTE_LINK_CONTROL=y in your prj.conf and include the header file. If you don't want the library to automatically to connect to LTE network on boot, you need to set the following: CONFIG_LTE_AUTO_INIT_AND_CONNECT=n 
 I think relevant functions for you to achieve what you want are for example: 
 lte_lc_system_mode_set(LTE_LC_SYSTEM_MODE_GPS);

lte_lc_normal();

// Do GPS stuff

lte_lc_offline();

lte_lc_system_mode_set(LTE_LC_SYSTEM_MODE_NBIOT);

// Blocking call, tries to connect for 10 minutes by default
lte_lc_init_and_connect();

// Wait for LTE connection...
 
 Best regards, 
 Jan Tore

Heidi · Answer

Hi! 
 
 Yes, there is. The AT command AT+CEREG? lets you read the network registration status, which will tell you if the UE has connected to the network. 
 You can use the AT command interface available in NCS to read out this information in your application. 
 
 You can read more about all AT commands available in the AT Command Reference Guide . 
 
 Best regards, 
 Heidi

Thingy91: Wait until connected

Top Replies