The National Instruments 778955-01 Interface Module, also known as the PXI-8331, is an advanced interface solution utilizing MXI-4 technology to enable seamless direct control of PXI systems from high-performance desktop PCs or servers. This high-bandwidth connection operates transparently with software applications and drivers, facilitating efficient management of PXI systems. The configuration involves two 778955-01 modules—one installed in the PC and the other in slot 1 of a PXI chassis—connected via a dedicated cable (not included). Users can acquire the necessary PCI board, PXI module, and cable separately or opt for a complete MXI-4 kit.

The MXI-4 technology supports flexible system designs, allowing multiple PXI chassis to be connected in either daisy-chain or star configurations. By installing the module in any peripheral slot of the master chassis and linking it to a second 778955-01 module in the first slot of a slave chassis, users can expand the available PXI or CompactPCI slots significantly, enhancing system scalability and versatility. This module operates as a PCI master/slave pair through the PCI-PCI bridge register set, establishing communication between two isolated buses over a fiber-optic or copper data link capable of transferring data at 1.5 Gbit/s. The features enabled by this cutting-edge technology include the ability to physically separate measurement or automation systems from host PCs, integrate PCI, CompactPCI, and PXI devices within a unified system, and effectively control a PXI/CompactPCI backplane from a PCI-based computer or another PXI/CompactPCI system.