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Keyboard Ghosting Explained

microsoft.com

11–20 of 99 posts

Re: Keyboard Ghosting Explained

#11
> The internal electronics on the SideWinder X4 use a variant of resistive multitouch technology. Each key has a screen printed resistor in series with its switch. This allows the internal electronics to read the state of each key switch independently for very large multiple-key combinations.

This is pretty vague. How exactly does this disambiguate which keys are being pressed?

Re: Keyboard Ghosting Explained

#12
post #7

Earlier quoted context omitted.

Beds and keyboards are deserving of discrimination. Personally, I adore my das keyboards.

http://www.daskeyboard.com/ All keyboards should have a couple of USB ports built in, that's a great idea.

Welcome to 1998 :) http://en.wikipedia.org/wiki/File:Apple_USB_Keyboard_B.jpg

Re: Keyboard Ghosting Explained

#13
post #4

This explanation is poor. The keyboard controller and interface are crucial. NKRO is possible, but can it can be flaky over USB. There are many variables involved. Want to learn more? Hit the geekhack forums (search for NKRO) or geekhack channel on freenode.

I wouldn't say the explanation is "poor." The article details one of the reasons behind the lack of n-key rollover. Note how the text explicitly limits the scope of the article.

> Typically, ghosting is the result of one or more of following three limitations: the hardware can't read the given key combination, the software on the computer doesn't support multiple simultaneous keys, or the communication protocol between the hardware and software limits the maximum number of simultaneous keys reported. The next section discusses in more detail the hardware design of typical keyboards that limits the number of keys that can be read at the same time.

The article also links to another page that describes the issue with USB: http://www.microsoft.com/appliedsciences/content/projects/Si...

Re: Keyboard Ghosting Explained

#14
post #9

In which cases are such keyboards necessary? I use a $3 one (which I bought to replace the one I used for over a decade) and I've never had such issues. I use this keyboard for coding and gaming, not just for common tasks which require low performance.

I use a Model M and sometimes encounter ghosting. Some types of gaming are worse than others. For example, while playing RTS or MOBA I do not encounter ghosting while playing FPS I encounter it on a regular basis.

This is because in RTS and MOBA while you might be rapidly hitting your keys you should be hitting them in succession, not simultaneously! In the FPS on the other hand you might be trying to walk forward and right while crouching and reloading, which requires four keys to do. This would cause problems for my keyboard.

Programming is more like the RTS than the FPS in this respect. You may be hitting a lot of keys, but the combinations are more likely to involve modifiers such as CTRL, ALT, or shift rather than a combination of letters.

Re: Keyboard Ghosting Explained

#15
When developing Flash games this was a personal hell. Many keyboards are unable to process Up+Left+Space, usually meant for shooting at northeast. In this case one of the keys is simply ignored. Worse yet the other directions work, so you get a hard to diagnose bug.

The users end blaming you for their character deaths and the overall experience is frustrating. The best solution I found was to use a different key for shooting, such as left Ctrl, 'a' or 'z'.

If you ever wondered why you can't use the large button on your keyboard to trigger the main action in a game, blame your keyboard manufacturer.

Re: Keyboard Ghosting Explained

#16
I like how they mention keyboard manufacturers using the term up to as a way to deceive customers, and then in the next paragraph mention the same phrase when referring to the Microsoft keyboard.

'Another marketing strategy is to state that the keyboard allows "up to" some large number of key presses.'

'Microsoft's SideWinder X4 features multitouch technology that allows it to detect, and report ANY combination of QWERTY keys, up to 17 keys.'

Re: Keyboard Ghosting Explained

#17
post #11

> The internal electronics on the SideWinder X4 use a variant of resistive multitouch technology. Each key has a screen printed resistor in series with its switch. This allows the internal electronics to read the state of each key switch independently for very large multiple-key combinations. This is pretty vague. How exactly does this disambiguate which keys are being pressed?

Given the detail that was put into describing the problem I too was disappointed with that last paragraph, though I wouldn't be surprised if that is all the author was able to get away with.

Re: Keyboard Ghosting Explained

#19
post #12
post #7

Earlier quoted context omitted.

http://www.daskeyboard.com/ All keyboards should have a couple of USB ports built in, that's a great idea.

Welcome to 1998 :) http://en.wikipedia.org/wiki/File:Apple_USB_Keyboard_B.jpg

And this was continuing the practise of Apple's previous Apple Desktop Bus keyboards (like the beloved M0116 http://deskthority.net/wiki/Apple_Standard_Keyboard ) which had ADB ports on both sides, mainly so that you could daisy-chain the mouse onto the keyboard. It's really dismal that this hasn't become standard on USB keyboards.

Re: Keyboard Ghosting Explained

#20

I like how they mention keyboard manufacturers using the term up to as a way to deceive customers, and then in the next paragraph mention the same phrase when referring to the Microsoft keyboard. 'Another marketing strategy is to state that the keyboard allows "up to" some large number of key presses.' 'Microsoft's SideWinder X4 features multitouch technology that allows it to detect, and report ANY combination of QW…

If I understand correctly, that's just a slight error of wording. They actually mean "any combination containing less than 18 keys".
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