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Gertboard

e14 Contributor over 13 years ago

Hi

I got the gertboard yesterday and been running some of the tests,

All worked well.But the board is very sentisive to noise,leds flickering when nearing a hand.

I think theres a ground problem somewhere !?

Anyone else has this problem or is my gertboard defect.

Jan

andytechman over 13 years ago

Hi Jan,

This is normal. The input buffers have no pull-ups so they are left floating if not being driven. According to the user manual:

"Depending on the type of 74xx244 buffer chosen, the LED could behave randomly if the port is not
driven properly. In that case it may easily switch state, switching on or off with the smallest of
electronic changes, for example, when the board is simply touched."

So your Gertboard is not defective

Andy
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e14 Contributor over 13 years ago in reply to andytechman

Hi
Thanks for your reply Andy
I connected a testwire from raspi usb powerconnecters sheild (GND) to the gertboard conn.j28,GND
This seems to help,i can now use the buttons without triggering a lightshow.
Jan
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