RAK4631 reset to DFU under RUI3

[psupine (Mark Jeffree)]

I have somehow managed to lockout the Arduino upload service to my RAK4631.

I think the issue is that the current app is hammering the serial comms over the USB channel so that I’ve implemented a DoS hack on myself. (Even in retrospect I can’t see the code pathway that’s doing this but … meh, it’s happening)

So I tried to get back to blank using the double tap reset, but without success. Is this supported under RUI3?

[Edit]
I found a solution. I typed “AT+BOOT” into the send buffer (Arduino IDE), reset the board and then hit to send the AT command to the board in the little window I had before it dived into it’s “hammer the serial interface” mode.

[beegee (Bernd Giesecke)]

Hi @psupine

RUI3 doesn’t have the double-press Reset to enter bootloader feature.
If the AT+BOOT doesn’t work (I was there several times), it is better to have a DAPLink ot JLink at hand to flash a bare AT command firmware.

[psupine (Mark Jeffree)]

Hi @beegee,

Thanks for confirming that.

My code will henceforth always include

“hello”; delay(1000);

in setup, so that the AT+BOOT window remains in place.

[psupine (Mark Jeffree)]

It’s a bit uncool to reply your own comment but consider this a public service announcement.

Putting that pattern of “hello” and delay immediately after the USB serial port is up but before anything else is run, thereby creating a window where AT+BOOT can be heard, has saved my bacon ten times today.

If you are experimenting with comms ports, I can recommend it completely.