The Stacked NIC_E board was developed for use in a multi-node 1393 FIRERING®. It is capable of transferring data at 2.5 Gbps using our fiber optic transceivers (HMP4-2500TX/HMP4-2500RX) or using optional coax mezzanine boards. Two Gigabit Ethernet Interfaces and one RS-232 port are provided for I/O. A set of differential SMA connections are provided for clock triggering and testing purposes. The board’s functionality is controlled by programming the onboard Xilinx Virtex-5 FPGA.