RAK3172 print <BOOT MODE> after reset

After im press reset, it show < BOOT MODE> in monitor
After im enter AT+BOOT?, it show AT not support. in monitor
After im click upload code, it show CCCCCCCCCCCCCCCCCCC
Please see it in this picture.


Please help me fix it.
This is first time upload code for this module, and not yet success.

If the device starts in bootloader mode, there is no application in the module.

What RUI3 version are you using?
How do you upload your application?

You can try to use AT+RUN command to start the application from bootloader mode and see what happens.

After enter AT+RUN it reply:

Stop Boot Mode

Jump failed. No legal application detected.

This module use RUI_BOOT_0.7_STM32WLE5CC

What I expected, there is no application on the device.

Did you try to flash an application?
Any error messages?
What application are you flashing? Is it one of our examples or your own code?

RUI_BOOT_0.7_STM32WLE5CC is the bootloader version only.

Try to flash the default firmware for the RAK3172 as described here: RAK3172 Module Quick Start Guide | RAKwireless Documentation Center

Im just want upload code blink led but can not do it in first time until now

Looking on your screenshot, the firmware flashing is interrupted, leaving the device without an application.

How are you powering the device?
How are you connecting to the UART?

Try to upload our default firmware, to check if the connection is stable and the device is not damaged.