Access GPIO on atom board

Question

On this machine: http://www.nexcom.com/ProductModel.aspx?id=376f4fa5-64f3-41d1-afba-60ee48883465

I'm trying to access gpio, but neither Nexcom or Intel support has been very helpful.

The closest I've come is this blog post which says I have to write my own driver: http://geekswithblogs.net/BruceEitman/archive/2010/08/01/windows-ce-using-a-driver-to-readwrite-hardware-registers.aspx

From the nexcom manual it states gpio port is located at 0EE4H (0xEE4). What am I supposed to with this info? Am I really supposed to write my own driver?

edit: is must work on windows xp embedded and windows 7 embedded.

Answer 1

You can't directly access hardware resources (like GPIO pins) from userspace processes unless there's a driver that exposes this functionality. This means that either you find a suitable driver (I have no clue about where to look for such a thing) or you write your own.

p.s. It may also be the case that your OS expose the GPIO pins somewhere. On a linux prototyping board I worked on once there were a few files (IIRC /dev/gpioX, with X being the number of the pin) you could read/write to if you had the appropriate permissions.

Answer 2

You need GIVEIO.SYS.

It actually comes from Microsoft originally.

when you install it, you specify what port addresses you want.

then the user space program can access the ports directly.

You unix bretheren can just call ioperm() instead with the process running as a root. A shame MS didn't do that, but GIVEIO.SYS is okay.