Testing II plus keyboard without computer....

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Testing II plus keyboard without computer....

I have a II plus clone keyboard I need to test to make sure it is working. I have an apple power supply but don't have a working motherboard. Can I simply breadboard up a 16 pin dip connector to the power supply and use a logic probe or will there be a problem? Is the keyboard enough load to let the switching supply work, or should I put a large wattage resistor in parallel to the keyboard? Will letting the keyboard decoder (it's actually a TMP8048P micro controller) have a problem with the "floating" output since it's not hooked up to a computer?

Thanks,
Corey

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Re: Testing II plus keyboard without computer....

Hello Corey,

You can find interesting information on the keyboard in the book Understanding the Apple II in pages 168-173.
I think the power supply will work with just the keyboard plugged in.
Finally, since the keyboard encoder just provide outputs, I don't think foating wires should be a problem.

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Re: Testing II plus keyboard without computer....

Thanks...

Great book, wasn't aware it was available on-line.

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