The 7I77 is daughtercard/breakout board for use with MESA's 25 pin I/O FPGA cards like the 5I25.  The 7I77 is designed for interfacing  up to 6 Axis of analog servo motor drives and also provides 48 isolated I/O points for general purpose field I/O use.  Six +-10V analog outputs and six encoder inputs (all with index) are provided for servo interfacing.  Six floating drive enable outputs allow control of active high or active low drive enables.  Encoder inputs can be individually set for differential or single ended mode.  48 points of isolated field I/O are provided for general control use including limit switch and control panel inputs, coolant enable and tool changer control outputs.  Isolated I/O includes 32 sinking inputs and 16 sourcing outputs. Inputs can sense 5V to 32V signals and the outputs can switch 5V through 28V signals.  Maximum output load is 300 mA.  Outputs are short circuit protected.  In addition to the being able to read digital on/off status of each input,  four input pin voltages are readable with 8 bit resolution, and two MPG encoder inputs are provided as an option on four field inputs.  Field I/O is powered by an isolated 10-32V field power source.  One RS-422 interface is provided for I/O expansion via a serial I/O daughtercard.  All field wiring is terminated in pluggable 3.5 mm screw terminal blocks.