control motors and sensors from pc in real time?

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Hello guys, right now i'm running orocos_toolchain in my xenomai patched linux(pc) for real time control of robot. And now i'm searching for the way to connect multiple motors and sensors with my pc to control them from my pc instead of buying some expensive microcontroller and than learning to use it from start . So does anyone knows here how can i do it? i.e how can i connect the motors and sensors to my pc and control it in real time?