STM32F407G-DISC1 is in reset when supplied from external +5V.

[GJuch]

Everything works fine when the USB programming port is connected to PC. 

When the board is supplied from external +5V then the reset signal is 

active all the time. The reset disappears when I connect USB programming 

port. It seams that the STM32F103C8T6 forces low the line T_NRST until 

it gets USB connection. 

Is this an expected behavior? What can I do to use the board without USB?

There is a solder bridge SB11 which connects T_NRST to the NRST of the 

main processor and I could remove it. But then I probably could not be 

able to upload new software through USB.  

[waclawek.jan]

Update the firmware in the STLink (STM32F103).

JW

[GJuch]

OK JW, how to do it? I am using Atollic TrueSTUDIO for STM32 ver.9.0.0.

[GJuch]

Done! I have found - Help / Tools / ST-Link Upgrade.

It is fine after the update .

Thank you JW.

Grzesiek

[Tesla DeLorean]

The V24 or V25 shipped on the STM32f407G-DISC1 would hold the target in reset.

Most current is V31 which is available as a stand-alone upgrade

https://www.st.com/en/development-tools/stsw-link007.html