The MESA 7I77 card set from Mesa Electronics (Richmond, CA) is a FPGA-based, 6-axis analog control system for CNC, industrial automation retrofits, and OEM systems. Six axes of analog outputs and encoder inputs are sufficient for up to 5-axis machines plus spindle control. Encoder inputs are individually programmable for TTL or differential mode. The PCI or PCIE host interface provides real-time access to the motion hardware. In addition to the motion-related I/O, 32 digital inputs and 16 digital outputs are provided. These digital I/O points are isolated from the system ground and can use 5V to 32V I/O voltage.
Inputs have a threshold of half the I/O voltage for high noise immunity. Outputs can supply 300 mA each, and are short-circuit-protected. I/O can be expanded to more than 400 I/O points with real-time access, or up to 12 motion axes. The card set is supported by LinuxCNC. All FPGA firmware is open source, and easily modified to support new functions or different functions.