keyboard limitations

Member
Posts: 35
Joined: 2009.01
Post: #1
Does anyone know why the keyboard only accepts 2 keys worth of input at any given time? Surely we've moved beyond the point where the connection cable can only carry 8 bits of information and bits need to be reserved for shift, option, control and command... Even then, 4 keys should have been able to make it through!

If I'm wrong and more than 2 keys can be accepted, please let me know. If not, is there any way to convince Apple's manufacturers to update this convention perhaps established in the late 80s? A petition, maybe? As far as I know, PC keyboards DO ACCEPT MORE KEYS! MadCryHuhSad
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Moderator
Posts: 1,560
Joined: 2003.10
Post: #2
This is a hardware limitation that varies by keyboard. For example, a Das Keyboard can process up to 12 individual simultaneous keypresses. It is a quite lamentable issue, but only comes up in a few cases, so it seems like it doesn't get enough attention for the industry to fix the problem.
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Member
Posts: 715
Joined: 2003.04
Post: #3
Certainly it accepts more than 2 keys.

Command Shift + 4 for instance for a controlled screen grab.
Command Shift +3 almost the same thing.

Quicktime has some four button press.
Command Control Option N for new audio recording.

Is it a limit of bluetooth? (worst invention ever, requires toxic batteries Mad)

Of course modern 'typists' use only a quarter of the letters to make words these days so maybe the
petition should be for electric shock treatment via the keyboard for people who do that.
I R makng a gme = zzzzzap!


If I hit four keys like so "afds", or "qrew" all keys input as you can see.
Can't really say I'm hitting every key at the same nanosecond that way, though.

Whoa, don't try hitting command control option shift plus a random key while posting in a forum...things will happen!
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Joined: 2003.10
Post: #4
Modifier keys are handled separately from other keys. That's why those particular 4+ key combinations always work. You can get a better look at what's going on by opening Keyboard Viewer (can be enabled in System Preferences > International > Input Menu) and mashing the letter keys.
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Member
Posts: 254
Joined: 2005.10
Post: #5
My understanding was that the keyboard is typically divided into sections and each section can only register some of the keys pressed at the same time. If you push keys from each section though, the key presses should make it through.
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Member
Posts: 715
Joined: 2003.04
Post: #6
Using that method I can get up to six keys pressed if I try to press 8 of them.
Sometimes...other times it just does five or four.

But again getting 8 keys pressed perfectly in synch is something for robots.

I don't see why you'd press more than four at a time on the regular keyboard.

Lets see:
Walking forward and sidestepping and shooting...and crouching and/or jumping?
What else do you want to do simultaneously at that point?

With WASD and a mouse the pinky would still be free to do a modifier.

I'm wondering if a joystick controller would be able to map that much action all at once.

Analog Left,+ Analog right + left bumper, + right bumper, + left trigger + right trigger, yeah...thats a great simultaneous combo to totally irritate a player.


Edit in response to Blacktiger:
Yes it seems some portions of the keyboard block multiple input.
The middle of the keyboard basically doesn't like you mashing keys.
And it seems to have something to do with the order of the press itself,
which happens in a split second.
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Member
Posts: 283
Joined: 2006.05
Post: #7
igame3d Wrote:I don't see why you'd press more than four at a time

Local multiplayer games - two or three people using the same keyboard. That's why games like Deimos Rising suggest that you use modifier keys as much as possible.
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Post: #8
StepMania (and derivatives) can also require up to 8 keypresses at once when you're playing on the keyboard.
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