Mr. Swiss, Dinosaur- Thank you for your replies. I'm looking forward to trying the SNC stuff out. Once I get the basic ability to access the ethernet port I'll see what I can do about the timing problem. I understand there's a realtime kernel for Ubuntu available, and maybe if I use that and shut do...

I'm looking at converting a DOS application to Linux. The program sends and receives a 64-byte ethernet packet between the PC and a machine controller every millisecond while the machine is in operation. This is not a network operation. The PC and the machine are just using the ethernet cable as a s...