I’ve just received my RAK5010, and I cannot get it to talk with me.
I’ve connected the USB port (which comes up as COM77), and opened it in Putty. No matter what character I type, I immediately get
“Invalid at command.
It can’t be an invalid AT command because I can’t get pass press the “a” key.
I’ve tried connecting a USB <-> Serial dongle to the GND, IO3, and IO4 pins. I get no output at all. I’ve tried swapping IO3 and IO4, still nothing. I’ve tried both with and without the connection to the VRef pin.