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Altera_Forum
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11 years ago

button with fpga pull up, gnd

I connected push button to gpio_1 pins on Altera DE2 board. In verilog code I assigned one button pin 'r' as ouput to gnd, another pin 'c' inout tri1 (pull up). I want to make inverter for 'c'...
Altera_Forum's avatar
Altera_Forum
Icon for Honored Contributor rankHonored Contributor
11 years ago

I recommend not trying and implement the internal pull-up in your source code. I don't think Quartus does anything with it.

Assuming you're using a DE2 board with a Cyclone IV device - in Quartus, in the Pin Planner, in the row with your 'c' signal in you need to turn the internal pull-up 'on'. Do this in the 'Weak Pull-Up Resistor' column. If you can't see this column by default right click anywhere in the column headings and select it to make it visible.

If it's a DE2 board with a Cyclone II device you can't do this.

Cheers,

Alex