Nios II Classic Processor Reference Guide

ID 683620
Date 10/28/2016
Document Table of Contents The D Flag

The D flag indicates whether the exception is an instruction access exception or a data access exception. During a general exception, the processor sets D to one when the exception is related to a data access, and clears D to zero for all other nonbreak exceptions.

The following exceptions set the D flag to one:

  • Fast TLB miss (data)
  • Double TLB miss (data)
  • TLB permission violation (read or write)
  • Misaligned data address
  • Supervisor-only data address