NI motion controllers have up to 64 bits of digital I/O that you can use for a wide variety of applications, such as opening or closing valves or turning on and off solid-state relays using the SSR adapter. You also can use the motion controller digital I/O through an NI universal motion interface (UMI-777x), which provides optically isolated, 30 V logic, digital I/O. NI motion controllers also have eight channels of 16-bit analog I/O, which are useful for high-performance analog measurements.
Figure 7: A typical motion control system needs high-performance digital, analog and motion I/O.
Encoder, DAC, ADC, and motion I/O resources that are not used by an axis are available for nonaxis or nonmotion-specific applications. You can directly control an unmapped DAC as a general-purpose analog output (±10 V). Similarly, you can use any ADC channel to measure potentiometers or other analog sensors. If you do not need an encoder resource for axis control, you can use it for any number of other functions, including position monitoring, or as a digital potentiometer encoder input or master encoder input for master/slave (electronic gearing) applications. Each axis also has an associated forward and reverse limit input, a home input, a high-speed capture trigger input, a position breakpoint output, and an inhibit output. You can use these signals for general-purpose digital I/O when they are not being used for their motion-specific purpose.