I'm often using arduinos or even raspberry pis for simple gpio stuff when playing around with my projects. However, arduino is somewhat slow for some things, and the pi is 3 volt and still somewhat annoying..<p>It seems it should be fairly simple to buy a PCI-E card with some gpio channels, but they all seem laughably expensive for what is indeed a very simple piece of tech.<p>Can HN recommend me a card, ideally, 5 volt tolerant, and ideally with 16 or more channels ?<p>I don't care about isolation or stuff like that, but I'd like it to be fairly responsive, so that I can for example create and respond to pulses of about 20 us, which is fast compared to what an arduino can do, but pretty slow compared to what I can achieve with an fpga.