OPT-0V Remove VME interface (for standalone)
OPT-1 4 additional channels axis interface circuitry
OPT-14 Replacement of flag opto isolators with socketed shunts
OPT-16 16K x 24 battery-backed parameter RAM
OPT-1S Additional 4-axis capability (Piggyback board)
OPT-1V 4 additional channels axis interface circuitry
OPT-4A 20 MHz CPU, zero-wait RAM, flash backup, no battery (~25% speed increase)
OPT-5A 40 MHz CPU, zero-wait RAM, flash backup, no battery (~125% speed increase)
OPT-5B 60 MHz CPU, ze flash RAM, no battery, buffered expansion port
OPT-5C 80 MHz CPU, zero wait RAM, flash backup, no battery, buffered expansion port