tldr: I'm looking for a keyboard (PS/2, preferably non-mechanical) with a high matrix scan rate to use for a university project.
My team and I are trying to build a setup that allows us to determine
when a key was pressed with as much precision as possible. This means reducing the latency between the key press and the registration of the event to a minimum. More specifically, constant latency (e.g. from debouncing) can be easily subtracted afterwards, so what we are really trying to avoid are variations in the latency.
We register keyboard events by connecting to an Arduino via PS/2, so the only big source of latency is the keyboard itself. The variation we've measured in our experiments is very close to what's to be expected from the matrix scan rate (~15 ms for our 75 Hz keyboards, ~10 ms for our 125 Hz keyboard); we're hoping getting a model with a higher scan rate will get us significantly lower than that.
So, do you have any suggestions for us? The keyboard should have a PS/2 connector (to avoid USB polling), not have a distinctive sound (we need it to sound "average", so I'm guessing no mechanicals?), and a low price would be a bonus (we need to justify the expense to our supervisor
).
