Why is the ATDB command always returning the same value from XB3 modules?

Any thoughts regarding why the ATDB command is always returning the same value (0x69) from my XB3-C-A2-UT-001 modules? I get the same value from 2 different modules,and have tested from 2 different locations. The cell signal strength should be changing.

I’ve experimented with ATDB0 and ATDB1 variants of the command also, and these commands always return (0x0E). Does this indicate a command error?

Thanks in advance,

Erik

Hi Erik,

Due to limitations of the u-blox SARA cellular module in the XB3-C-A2-UT-001 module, the ATDB command is only able to represent ranges of signal level, such as -105 or lower, -93 or lower, -81 or lower, etc.

Furthermore, on an LTE device, the ATDB value (RSSI) is not the best indicator of signal quality. Instead, use the ATSQ and ATSW commands to read the signal power and quality (RSRP and RSRQ).

Thanks very much for the clarification and suggestion.

When I send the ATSQ or ATSW commands, I always receive 0x0E in response. Does this mean that these commands aren’t defined in the module version that I have, or something similar? Thoughts?

Can you clarify? Are you running the commands in command mode or API mode? If API mode, can you post the full API frame you receive (e.g. something like 7E 00 06 88 01 53 51 00 0E C4).

Also confirm that you have updated the XBee 3 Cellular module to the latest available firmware (11415).

The commands are being run in command mode.

The cell modules have the “as received” firmware on them, which is 11413. I take it that the firmware needs to be upgraded to use the ATSQ and ATSW commands?

Yes, you need to upgrade the firmware to use ATSQ and ATSW. Documentation for upgrading using Digi’s XCTU tool can be found in the user guide here: https://www.digi.com/resources/documentation/Digidocs/90002258/#concepts/c_update_cellular_and_device_fw.htm

Also be sure to review this page: https://www.digi.com/resources/documentation/Digidocs/90002258/#tasks/t_update_fw_plan.htm