National Instruments NI cDAQ-9401 8 channel TTL I/O Module

National Instruments NI 9421 cDAQ Digital Input Module

National Instruments NI 9411 cDAQ Differential Digital Input Module

National Instruments NI USB-6525 – Isolated Digital I/O Device / USB Interface

National Instruments NI 9401 8-Ch 5V TTL Digital I/O Module Compact DAQ

National Instruments NI 9401 8-Channel TTL High Speed Digital Input/Output

National Instruments NI cRIO-9411 6-Channel Differential or TTL Digital Input Mo