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Altera_Forum
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16 years ago

I2C via GPIO-bit-bang on Linux/Nios

I have been getting Linux up and running on a Cyclone III. Overall, things were going smoothly. I got the reference design running, added an extra UART and some GPIO and everything came together ri...
Altera_Forum's avatar
Altera_Forum
Icon for Honored Contributor rankHonored Contributor
16 years ago

I think I figured out my own problem. I had been using the PIO peripheral provided by Altera with SOPC Builder. I needed to download the Linux-specific gpio block from the ip library that is on the nioswiki. It has a completely different register map that is more amenable to bit-banging. (It uses one register to handle all the functions for each GPIO pin, not one register that handles a single function for up to 32 pins.)