Advanced SEU Detection Intel® FPGA IP User Guide

ID 683542
Date 3/26/2019
Document Table of Contents

2.2.4. SMH Lookup

The .smh file represents a hash of the CRAM bit settings on a design. Related groups of CRAM are mapped to a signal bit in the sensitivity array. During an SEU event, the application can perform a lookup against the .smh to determine if a bit is used. By using the information about the location of a bit, you can reduce the effective soft error rate in a running system.

The following criteria determine the criticality of a CRAM location in your design:

  • Routing—All bits that control a utilized routing line.
  • Adaptive logic modules (ALMs)—If you configure an ALM, the IP core considers all CRAM bits related to that ALM sensitive.
  • Logic array block (LAB) control lines—If you use an ALM in a LAB, the IP core considers all bits related to the control signals feeding that LAB sensitive.
  • M20K memory blocks and digital signal processing (DSP) blocks—If you use a block, the IP core considers all CRAM bits related to that block sensitive.