Expansion Headers for Cyclone 5 eval boards

Linux Kernel
1

Is there any good reference on how to map/use the expansion headers in Cyclone 5 eval kits? I am using Terasic Cyclone 5 eval with 2x20 expansion header. And I want to use several expansion pins as raw GPIO.

I’m running on Linux, where I am already able to read the values from the switches (raw GPIO) and set values for LEDs. But I can’t seem to get the expansion header pin into GPIO mode, primarily as input mode. The datasheet of this kit is indicating the expansion headers are mapped to GPIO1. But I always read 0 from GPIO0, GPIO1, or GPIO mapped addresses.

What am I missing (pinmux?) ? Or where should I check (repos) for good reference?

2

From the top of my head the GPIO isn’t fully memory mapped to the HPS.
You’ll need to configure that yourself using Platform Designer.

Which board exactly are you using?

3

I am evaluating Terasic’s ADC_SOC board (Cyclone V) and you might be correct that GPIO isn’t fully memory mapped to the HPS.
I’m not well versed with the platform designer, though. But I only see 3 PIO in their Platform designer file or qsys (LED, BUTTON, and SWITCH). So if I were to add a new memory map for say GPIO1’s first 8 bits, which part of Quartus or Platform designer will tell that the new PIO is now mapped to a specific GPIO?