The National Instruments part number 779929-01 refers to the PXI-6682, a sophisticated PXI Timing and Synchronization Module designed for high-performance timing and control applications. This module occupies one 3U CompactPCI slot within a PXI chassis and features an input frequency range from DC to 30 MHz, allowing for precise clock signal routing with minimal skew across multiple devices in a PXI system. The module is equipped with three SMB general-purpose PFI lines capable of handling various synchronization tasks, and it supports synchronization technologies such as IEEE 1588, IRIG-B, and GPS.

On the front panel, users will find essential connectors including a GPS antenna connector, CLKOUT, CLKIN, and multiple PFI connectors, alongside status indicators for GPS synchronization, Ethernet link, and speed. The CLKIN input operates at a 10 MHz fundamental frequency, accepting sine or square wave signals with a voltage range of 400 mVp-p to 5 Vp-p and an absolute maximum input voltage of 6 Vp-p. This device functions as a high-accuracy, free-running reference clock and can timestamp input events according to the synchronized system time. The programmable clock operates from DC to 1.5 MHz, and the module utilizes NI-Sync software for programming, compatible with NI application development environments such as LabVIEW, LabWindows/CVI, or Visual C/C++. It is typically installed in slot 2 of the PXI chassis to optimize its control capabilities over timing and synchronization features, enabling users to manage active-low digital signals effectively.