On Jan 22, 2012, at 2:08 PM, Eric Smith wrote:
Chuck Guzis wrote:
But many PC keyboards implement [n key rollover]
also.
The USB HID spec stupidly limits USB keyboards to reporting a maximum of six
key depressions. I have not seen *any* USB keyboards with diodes or other antighosting.
Maybe some of the high-end "gaming keyboards" do.
Das Keyboard, interestingly enough, claims to support n-key rollover when run in PS/2 mode
and 6-key rollover in USB mode. Presumably it has the proper anti-ghosting hardware,
though I do not own one and have never looked inside one.
Fun question: I have an Apple Extended Keyboard II running through an iMate (ADB to USB
converter) to my machine. It's great, except for the word (or syllable, as it's
frequently found in words) "out". If I type it exceptionally fast, I get a
ghost on the semicolon (e.g. "ou;" or "ou;t", sometimes it sees the T
and sometimes not).
I'm assuming this is a ghosting issue in the keyboard itself, but I don't recall
it from when I used it natively on an ADB machine. Of course, it's been years since
I've used it natively on an ADB machine (I use crappier keyboards on them these days),
so it's possible I'm just a faster typist now. Is anyone else familiar with this
problem? Is it just the iMate? I would be surprised.
- Dave