The National Instruments PCI-6516 Digital I/O Device (Part Number: 779082-01) is engineered for high-performance digital control applications. This device features a configurable watchdog clock designed to ensure system safety by setting outputs to predefined safe states in the event of a product failure, framework crash, or loss of communication. If the PCI-6516 does not receive a watchdog reset command within the specified timeout period, it will automatically transition outputs to a client-defined safe state, maintaining this state until the watchdog is disabled, the device is reset, or the computer is restarted. The watchdog timeout can be configured for periods up to (232 – 1) × 100 ns, approximately seven minutes.

The PCI-6516 has 32 source output lines that utilize photocouplers and Darlington pairs for connection to external signals. Users can connect a control supply ranging from 5 V to 30 V to the VCC terminal, while grounding the COM (GND). The device registers a logic high for any DC voltage of at least 11 V on the input terminals, while voltages below 4 V are interpreted as logic low; voltages between 4 V and 11 V yield an invalid reading. Isolation is provided on a bank basis, and the device supports a maximum input voltage of ±30 VDC with an input current of up to 12.5 mA per line. Communication is achieved via a 37-pin male D-SUB connector.

With a compact design measuring 5.54 in × 4.47 in and a weight of 2.5 oz, the PCI-6516 operates on power requirements of +5 and +3.3 VDC, consuming 250 and 300 mA respectively. The device is supported by NI-DAQmx driver software and is accompanied by a user manual available for download. The PCI-6516 is backed by a 2-3 year warranty, and for purchasing information, please contact a sales representative for a quote.