PCIe400 generic readout board qualification test

Abstract: The PCIe400 is a generic board for high-throughput data acquisition systems in high energy physics experiments. Its purpose is to interface up to 48 bidirectional links, supporting custom protocols at 1 to 26 Gbit/s, to modern commercial back-end links providing 400 Gbit/s bandwidth. It also targets clock distribution with phase determinism below 10 ps peak-to-peak. It has been designed for LHCb LS3 enhancement upgrade with experimental features to prepare LHCb Upgrade II, foreseeing an aggregated throughput of 200 Tbit/s. However, its versatility allows it to be used in several experimental environments. The board embeds Altera's flagship Agilex 7 M-series FPGA with a PCIe Gen 5 interface and an experimental QSFP112 serial interface. We present the results of qualification tests performed on prototype boards and the challenges encountered to meet specifications. Section 1 describes board-level validation, including power-up behavior and peripheral access. Section 2 focuses on high-bandwidth interface qualification through BER measurements. Finally, Section 3 investigates phase determinism in Agilex transceivers, a key requirement for precise clock distribution.