AnsweredAssumed Answered

F030F4 - not programming with Vcc>3V

Question asked by smith.chris.004 on Feb 28, 2015
Latest reply on Mar 2, 2015 by Clive One

I am facing very strange behaviour with uC mentioned in the topic. After connecting the microcontroller to the 3V3 supply and the SWD (IO, CLK, NRST and GND) on the Nucleo board, I get this error in ST-LINK Utility: "Internal command error". 

After a lot of trials I've found out that after lowering the supply voltage below 3V, the debugger is connecting properly.

I've tried different board as a programmer (F4 Discovery), even microcontrollers from 2 different suppliers, without luck. Of course supply pins are properly connected and with decoupling capacitors. Pulling up or down BOOT0 and NRST didn't change a thing.

What is cause of this behavior? I need to use 3.3V supply on my board, <3V is a no-go for me.