Space launch data recorder

One of the main tasks of a test and measurement system is to record as many measured values ​​as possible. In this context, the advantages of FPGA-based solutions such as inherent parallelism, extremely high bandwidth, flexibility, support for a wide range of interfaces, and an integrated CPU come into play. If the FPGA core board module is used as the basis for the hardware design, the additional hardware design is usually reduced to the development of a simple carrier board with low complexity and only a few components. This approach significantly reduces project risks, development time, and costs.

All this convinced the end customer to commission Enclustra to develop a data logger to upgrade an existing measurement system. To minimize development time, Enclustra's FPGA experts started the development of a carrier board for the Xilinx Zynq UltraScale+ based Mercury+ XU8 core module in parallel with the firmware and software development. Linux, as the operating system on the FPGA-integrated quad-processor system, had the task of reading and writing data on the SSD hard disk. Ext4 was used as the file system for the log data. Since the Linux Board Support Packet (BSP) was provided free of charge for Mercury+ XU8, the decision to use this technology was made quickly.

Two other key technologies also help reduce the time and effort invested in development. Enclustra always uses IP cores as much as possible during firmware development to avoid reinventing the wheel a second time and solve problems as efficiently as possible. Temporary storage of measurement data, before writing to the SSD disk, is implemented using the virtual FIFO of the stream buffer controller IP core. This IP core can manage up to 16 independent data streams simultaneously and supports up to 4GB of memory size, which is enough to meet almost all requirements.

The software is based on ASP.NET Core and written in C#, which enables the data logger to be integrated into the existing network infrastructure in record time. By using the Web API, the data logger can be controlled by upstream systems via the network. The native, state-of-the-art Web GUI based on ASP.NET MVC including Razor Pages has proven to be very helpful during the start-up process.

In a very short time, the project team implemented a system with two SATA SSD hard drives (with hot-swappable interface). The system can continuously record and access measurement data at a speed of 800MB/s. The flexibility of FPGA technology also allows to design the system in another way, that is, the SATA hard drive in the M.2 interface can be replaced by a faster NVMe hard drive later.

Due to the platform design of Enclustra's standard core board module and baseboard, this data logger can be quickly upgraded from XCZU4CG to XCZU5EV or XCZU7EV when more logic resources are needed, just by replacing the core board module through plugging and unplugging.