How many keys can be mashed at once on the keyboard and still have them register to the computer.

I heard that keyboards have matrices of keys wired to diodes and most have like 3-6 diodes .. so you can hold down for example wghl on some cheap keyboard as each key is on a different matrix, but you couldn't hold down 'weds'.

So hard core gamers get keyboards with n-key rollover, meaning if they're holding like all four arrow keys and 5 number keys .. they all still work.

Me, I want to learn steno as shown here:

They say it's possible to get to 225 wpm for most people .. some do 360 wpm and the record is like 600 wpm.

it works by mashing multiple keys at once to make words and phrases, max of 22 keys at once (you don't actually need 22 fingers, as long as at least one key is down the whole time, it's considered a 'chord').

I'd like to know how many diodes and matrixes does the typematrix have ? how many keys can I mash :)

Also, it'd be great if a futre version had n-key rollover if the current one doesn't (which I hope it does already).

You can learn steno yourself with 'plover-fly': http://plover.stenoknight.com/2011/12/fly-plover-fly.html

Thanks for reading.