I'm getting blanks when I try to send the "ATDB" command to the modem, whether it's XCTU or running MicroPython, but sometimes it works, so I'd like to know why. According to the statement below (which I lifted from another thread) the DB command returns blank when it has not received a signal strength from the cellular component, but what does that mean? The reason I ask is it seems to be random whether I get blanks or valid data, and I need to find a reliable way to read it every time so I can use it for diagnostic purposes in the field. If I successfully invoke the isconnected() member function in MicroPython after instantiating it with the network.cellular() construct, will that ensure that I get a valid DB reading every time or are there other factors/configuration parameters I need to think about?
From the manual https://www.digi.com/resources/documentation/digidocs/PDFs/90001541.pdf
DB (Cellular Signal Strength)
Reads the absolute value of the current signal strength to the cell tower in dB. If DB is blank, the XBee
Cellular Modem has not received a signal strength from the cellular component.
DB only updates when the modem is registered with the cellular tower. It is updated periodically, and
not when read.