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358
March 2002 Release
1-800-255-7778
Virtex-II Pro™ Platform FPGA Documentation
Chapter 2:
Operational Concepts
R
Reserved Book-E Instruction Class
The
reserved instruction class
consists of all instruction primary opcodes (and associated
extended opcodes, if applicable) that do not belong to either the defined class or the
allocated class.
Preserved Book-E Instruction Class
The
preserved instruction class
is provided to support backward compatibility with previous
generations of this architecture.