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Altera_Forum
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14 years ago

Weak pull-up resistors

Hi everyone! I enabled weak pull-ups for the input and output pin (cyclone II device). But when I measure the voltage on these pins, on the input pin is 3V and on the output pin is 0V. Shouldn...
Altera_Forum's avatar
Altera_Forum
Icon for Honored Contributor rankHonored Contributor
14 years ago

Hi Nikola,

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I defined the pin in the entity as GPIO: OUT STD_LOGIC := 'Z'

and after programming the device, the output pin is pulled to 3V.

--- Quote End ---

Great!

--- Quote Start ---

I still wonder why it is not pulled to 3.3V, but anyway it is still better than pulling it to GND.

--- Quote End ---

Try driving it high; is it still 3.0V or is it closer to 3.3V?

Cheers,

Dave