Construction of a PXIe platform for instrumentation development

PXIe is a modular instrumentation standard used in building electronic test equipment and modular laboratory instruments. Built on the PCIe bus standard, it provides high-speed transfer rates suitable for a wide range of applications. Instrumentation applications such as magnetic resonance imaging (MRI), generally has a high entry barrier due to high speed requirements and complexity. PXIe provides a good backplane option as the PCIe bus provides significant data bandwidth. However, the platform is inherently complex, usually contains proprietary IP and the solutions provided by vendors are often prohibitively expensive for some projects. To overcome these barriers, an open source PXIe platform has been developed. This consists of a PCIe I/O IP block for peripheral boards together with an associated device driver and application programmers interface (API) for the PCIe root complex hosted by the system controller. The design is capable of performing system controller initiated DMA transfers over PCIe in both directions. To further simplify system development, much use has been made of Xilinx based System on Module (SoM) units available from several vendors. Our example solution consists of (a) a PXIe system controller housing a Zynq based SoM mounted on a carrier board and running Linux and (b) a peripheral board based on an Artix SoM mounted on a carrier board and also hosting an FPGA Mezzanine Card (FMC) connector for further expansion.