Fixing B-L475E-IOT01A board for reset.

There are at least two revisions of the B-L475E-IOT0A board. Earlier boards (version C) have rather critical bug in the hardware, so the STLink-V2 does not work. This is because the NRST net between STLink and the main MCU is missing in the version C board. For more information, check the manual. Unfortunately the manual didn't describe how to fix it, although it is rather straightforward.

Grab a soldering tools and connect two points shown below.

On the schematic these two points correspond to

and

Now, you should be able to run the hello_world example without problem.

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