An apparatus for communicating between lock step is incorporated on two or
more processors operating in a lock step mode. Each of the processors
includes processor logic to execute a code sequence, and an identical
code sequence is executed by the processor logic. The apparatus further
includes a processor-specific resource referenced by the code sequence. A
multiplexer is coupled to the processor-specific resource, and is
controlled to read data based on the identification. Coupled to the
processors is a lock step logic block operable to read and compare the
output of each of the processors. The lock step logic determines if
operation of the processors is in a lock step mode or in an independent
processor mode. Such determination may be made by the lock step logic
turning off, for example.