Hacker News new | ask | show | jobs
by anonova 4640 days ago
It is hardware related. USB has a maximum rollover limitation of 6 keys + 4 modifiers. Though keyboards can have n-key rollovers (i.e., greater than 10 keys simultaneously), you have to use PS/2.

See https://en.wikipedia.org/wiki/Rollover_(key)
1 comments
ekns 4640 days ago
I don't know the details, but it is possible for a USB keyboard to support N-key rollovers. As an example: http://www.corsair.com/en/support/faq/vengeance-gaming/
link
Groxx 4639 days ago
Do they require custom drivers? I see no reason you can't have all-key rollover with that, unless the OS refuses to do so.

Not that I'm saying you're wrong, I really don't know if normal driverless keyboard input is capable of this. I certainly hope so. I just see essentially all 10-key rollover (or more) keyboards using PS/2 and citing that it doesn't work through USB.

link