Configuration
The GX799x (PCI to PXI) provides a transparent interface between a PCI host computer and a PXI chassis. The GX799x-1 (PXI to PXI) provides the same performance between a PXI master chassis and a PXI slave chassis. Multiple bus expanders can provide for unlimited I/O.
Most memory intensive PXI products such as the GX5xxx family of digital I/O boards use burst transfers. Burst transfers are performed at full bus speeds with a maximum throughput of 132 MB/s; these products are therefore unaffected by the added PCI bridge.
Standard data transfers using the GX799x incure a bus latency of 270 ns. PXI products that do not use burst transfer are typically unaffected by the latency (e.g., a switch card with a 5 ms relay closure time or a DMM with a 1 ms sample rate is unaffected by a bus latency of 270 ns).
The GX799x bus expanders for PXI systems, provide direct control of the PXI chassis from a desktop computer or from another chassis. The GX799x provides a transparent hardware and software interface to the PXI bus using PCI bridge technology and includes a two-card set (a host and a PXI backplane controller).
