The New 254-U2 with PCIe Gen 4

FPGA Computational storage PROCESSOR (CSP)

BittWare's 254-U2 Accelerates NVMe FLASH SSDs by Sitting Alongside as another U.2 Module

What is Computational Storage?

SNIA defines several components collectively called “computational storage.” For a typical 254-U2 deployment, the acceleration tasks are called CSS (computational storage services).

For example, the 254-U2’s Xilinx FPGA can perform compression much faster than a CPU—even surpassing the transfer rate of the storage system for transparent compression.

What is a CSP?

CSPs (like the 254-U2) work alongside FLASH, providing accelerated computational storage services (CSS) by performing compute, such as compression or encryption. This lets users build out storage using standard SSDs instead of being locked into a single vendor’s FLASH storage.

What features make the 254-U2 a powerful CSP?

  1. PCIe Gen4 interface for twice the bandwidth of Gen3-based solutions.
  2. Optional NoLoad provides a ready-to-deploy solution from Eideticom.
  3. Xilinx Kintex KU19P FPGA with 1.8M logic cells.

Generation 4.0

Double the Bandwidth!

Built with the latest PCIe Gen4 interface, the 254-U2 can transfer up to twice the bandwidth of Gen3 devices.

Solution Feature: Eideticom's NoLoad™

NoLoad Transforms the 254-U2 Into a Powerful CSP That's Easy to Deploy

  • Deployable enterprise-class solution
  • Choice of user-space or kernel-space implementation for minimal software changes

FPGA Hardware Components

NoLoad provides FPGA IP and host components. For the FPGA IP, you can see in the diagram the main components. More details are below:

  • NVMe Front End. The PCIe endpoint, NVMe Controller, and DMA Engine are all implemented in hardware and support PCIe Gen4 x4 for the 254-U2’s standard U.2 interface.
  • CSS Functions. The orange components are hardware-accelerated computational storage services (CSS) such as compression or encryption.

Host Software Components

As a complete solution, NoLoad provides host software with a choice of implementation:

  • libnoload. By modifying the application to use the libnoload library, the OS can remain untouched.
  • NoLoad FS. Another option uses the NoLoad FS (file system) as a shim on top of traditional file systems. The advantage here is user applications need zero changes to take advantage of accelerated storage.

Block Diagram, Data Sheet and Specifications

Board Specifications


  • Xilinx Kintex UltraScale+
    • KU19P in an FFVB2104 package
    • Core speed grade -2
  • Contact BittWare for other FPGA options

On-board DDR4 SDRAM

  • One bank of DDR4 SDRAM x 72 bits
  • 8GB bank (16GB version also available)
  • Transfer Rate: 2400 MT/s

Host interface

  • PCIe Gen4 x4
  • U.2 Connector
  • Compliant to SFF-8639

Datacenter deployment

  • On-board NVMe-MI compliant SMBUs controller (Spec. 1.0a)
  • Field flash update via software or SMBus
  • SMBus FPGA flash control: anti-bricking, fallback and multiboot
  • SMBus access to unique board data and temperature sensorC

Back panel features

  • User LEDs accessible
  • Reset switch to restore factory settings

Development features

  • JTAG connector for access to the FPGA, flash and debug tools
  • GPIO connector

Power supply monitoring and reporting

  • Voltage monitoring
  • Temperature monitoring
  • Fault condition reporting to FPGA


  • U.2 drive case optimized for cooling with passive heatsink


  • Hot swapping tolerant
  • On-card power derived from U.2 supplies
  • Power dissipation is application dependent
  • Typical FPGA power consumption ~20W
  • Card designed to deliver up to 25W power consumption


  • Operating temperature: 5°C to 35°C
  • Cooling: air convection


  • Manufactured to ISO9001:2008 IPC JSTD-001 -Class III
  • RoHS compliant

Form factor

  • U.2 compliant 2.5” Drive Form Factor
  • Height: 15mm

Development Tools

FPGA development

  • BIST - Built-In Self-Test for CentOS 7 provided with source code (pinout, gateware, PCIe driver and host test application)

Application development

  • Xilinx Tools - Vivado Design Suite HLx Editions: HDL and C/C++ with HLS


  • 254-U2 FPGA board
  • Built-In Self-Test (BIST)
  • Eideticom NoLoad pre-installed (optional)
  • 1-year access to online Developer Site
  • 1-year hardware warranty
  • Contact BittWare for extended warranty and support options

Interested in Pricing or More Information?

Our technical sales team is ready to provide availability and configuration information, or answer your technical questions.