SWD connexion for custom board

[DCarr.1]

I have an ST link V2 and a custom board running at 3.3V generated by an on-board regulator powered from a battery. Google is sending me mixed messages about connecting VAPP (pins 1 and 2) on the ST link to VDD on the board.

I'm a bit worried about destroying either my board or the ST link, so should I connect them or not?

[Uwe Bonnes]

VAPP on the STLinkv2, at least on the embedded versions, only measures the voltage. I do not know if it does voltage translatiion on a V2 standalone. So I see no danger,

[TDK]

On the 20-pin connector? Pin 1 is for the target voltage, so should be connected.

[DCarr.1]

ok thank you both very much.