My goal is to develop with the 4G module. I am powering the board with a battery.
However, I observed some strange behavior:
Occasionally, when I connect the battery, the two indicator LEDs on the RAK5860 do not light up, even though the battery is fully charged.
On the same base board, if I unplug the battery and plug it back in, sometimes both LEDs on the RAK5860 still fail to turn on.
In another case, when I connect the RAK5860 to a different RAK19007 board and power it with a battery, the LEDs also do not light up.
Is this expected behavior, or could it indicate a hardware issue? Do I need to follow a specific power-up sequence when using the RAK5860 with a battery?
Thanks for the suggestion. I tried your advice and flashed the BG77_Unvarnished_Transmission example onto the RAK4631. I am powering the board with a battery, but the LEDs on the RAK5860 still do not light up.
To double-check, I also tested the RAK5860 on several different RAK19007 baseboards. Interestingly, the module only powers up (LEDs on) on one of the baseboards. On the others, the RAK5860 does not start at all when powered from a battery.
Does this indicate a possible hardware issue with those baseboards, or could there be another factor (e.g. voltage/current delivery differences) that I should check?
ok, after some testing, I think the issue is not with the RAK5860 but with the check for a serial connection (which is missing without USB being connected). If your code checks for a serial connection using something like while(!Serial) the it will block code execution if USB is not present. Try removing the check for serial and see if that helps.