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Nucleo-F756ZG ST-Link LED Constantly Toggling in Debug Mode

Associate III

The LD4 on my Nucleo144 board with F756ZG on it constantly toggles when I enter debug mode. First it fast toggles for 5-6 times, then remains green for less than half a second, then repeats this sequence.

This happens in all cases (idle mode, stepping through, running) and stops only when I enter debug mode (LD4 stays red). Is there any way to stop this behaviour? Because LD4 is very bright and this quickly becomes an annoyance if you have Nucleo board on desktop near you.

As far as I remember, it was usually so that in debug mode, if you were in idle mode, so was this LED. And if you step through, in only toggled once. And if you put debugger into continuously running, then this LED would also continuously toggle.

Principal III

> Is there any way to stop this behaviour?

a piece of black tape on the LED or coloring with black marker pen.

- my solution to annoying bright LED. 🙂

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