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how can i make a controle station out of a pc keyboard? Answered

i wanna be able to make a keyboard, to work as a contole station so when you press a button, an action will activate, and when you press it again, it will deactivate?

so for an example, when you press "A" a led will turn on, and when you press "A" again, it will turn off. and then controle lots of led's.

just to let you know, its not just for led, its just an example.

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nothinn

7 years ago

im not looking for something that can take the signal the keyboard sends, but something that activates by a quick pulse of elecktricity, im thinking by sending 5 volt through all the keys.

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orksecuritynothinn

Answer 7 years ago

I'm sorry, but I'm still not understanding what you're trying to do here. You want all the keys on the keyboard to do the same thing? If so, what's the point of using a keyboard?

You can't "send 5V through all the keys" without a fair amount of reworking of the circuitry -- basically, you'd need to rip out the existing scan chip, feed one axis of the key matrix with 5V, and watch for 5V appearing on any of the lines for the other axis. You'd pretty much ruin the keyboard for other uses, of course.

And even so, that would just convert the keyboard into a giant pushbutton; you'd need to implement the alternating on/off operation separately. And depending on what you're trying to control, you might still need some driver circuitry or a relay to avoid cooking the keyboard.

If you told us what you were actually trying to build, we might be able to give you better advice on how to build it. Given what you've told us, it's hard to offer much useful advice.

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nothinnorksecurity

Answer 7 years ago

well, the keyboard is just for the look. its intended to be a lot of momentary switches, and ive already found out how to do that. what i wanna know is, a way you can send 5 volt through something, and it will let another current through, and then when you send 5 volt through again, it will stop the other current. it should work a little like relays, just not with a constant stream of power.

im intending on using it for starting and stopping different motors, LED's and other stuff.

if it helps, it doesnt have to be an entire keyboard, just the NUM pad on the right.

and it could also be so that when you press "1" you start a motor, and when you press "2" you shut the motor off.

and thanks for trying to help. :)

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orksecurity

7 years ago

You need something that will understand the serial signals the keyboard sends when you press, and then release, a given key. If you don't want to dedicate a full PC to the task, that probably means a microcontroller. Circuit designs and code samples to read from a keyboard are available for most (probably all) of them. You'd also need whatever circuitry is needed to interface the microcontroller's outputs to whatever it is you want to control -- the details will depend on what that is.

If you don't want to deal with that complexity, punt the keyboard and just buy a set of push-on/push-off switches. If you wanted to, you could sacrifice a junk keyboard and glue the keytops to these switches, creating something that looks like a keyboard for style's sake but uses this low-cost/low-complexity circuitry.