Does mister work with kv260 boards "out of the box" or is the official mister target a de10 nano? (I love my mister, assembled oneba few years ago). I don't follow the project closely due to zero free time these days
You have to base your build around either the DE10-Nano or one of the clone boards from QMTech. If I were getting into MiSTer I would skip faffing around with dev board builds and just get a SuperStation One, and I say this as someone who has two MiSTer builds based on DE-10 boards. In my case I'm using a MiniITX motherboard that the DE-10 plugs into called the IronClad Plus. The SuperStation one is apparently awesome. Great IO options, reference quality analog video, and nice industrial design.
The latter. Official MiSTer targets the DE10 nano.