Help to upload sketch to RAK3172

Check AT+VER =?

Now i trying upload LORA_P2P.ino from example

i’t have been trying connect 3.3V to BOOT0 nothing.

What mistake?

Boot0 is only required when you are uploading with STM32CubeProgrammer.

Any other method using UART2 (WisToolBox, ArduinoIDE, uploader_ymodem.exe) YOU MUST NOT PULL BOOT0 TO 3.3V. It forces the STM32 bootloader and our upload method does only work with our bootloader.

Thanks, but when not pull BOOT0 TO 3.3V not working too…

Try to connect to the device over UART2 with a terminal, 115200 Baud.
Send the command AT+BOOT (with CR and LF)
It should respond with
Disconnect the terminal, but leave the RAK3172 powered up.
Then try again to upload the code


  • UART2 with a terminal, 115200 Baud. === OK
  • Send the command AT+BOOT (with CR and LF) ==== OK
  • response == OK
  • Disconnect the terminal, but leave the RAK3172 powered up. ==OK

No results(

I have it

Are you sure the connection to UART2 is correct?

RAK3172 UART-USB converter

Are you sure the 3.3V and GND connections are good?

Make sure Boot0 is not connected to anything when powering up or resetting the device.

Yes. Commad like AT working and recived ansewer. that means connect corrent.

May be this ?

Command anser good

But when i send AT+BOOT response like this


nothing to work…
please help)

Try (1)
After sending AT+BOOT, switch your terminal to 9600 Baud and send AT+VER=? (with CR/LF)

If you get a response on that one, try (2):

Download the RAK Device Firmware Upgrade Tool
Download the RAK3172-E_latest.bin
Connect the device
Start the DFU tool, set the correct COM port, set the baudrate to 9600 Baud, select the downloaded BIN file.
Try to flash the firmware with 9600 Baud.

it try the same on 9600 not responce

look what respose on AT+BOOT. something wrong… i thinking my adapter do not good work

Thanks a lot. it working.
my USB2TTL give 5.V not 3.3V

Thanks beegee!