I'm trying to make a program that controls a six ways multivalve. The valve is controled using the PCI-6221. The program reads certain number from a serial port, when it is high enough the valve should change to another way. In short periods of time it seems to work, the problem is that when it has worked for several hours PCI-6221 seems to be inactive, as the program acts as if the valve has changed but it hasn't.
How can i solve this?
What valves are you using? Can you share your code?