A data processing system (10) has a system debug module (19) coupled to a
processor (12) for performing system debug functions. Located within the
system, and preferably within the processor, is debug circuitry (32) that
selectively provides debug information related to the processor. The
circuitry identifies which of a plurality of registers (26) is sourcing
the debug information. A user-determinable enable and disable mechanism
that is correlated to some or all of the registers sourcing the debug
information specifies whether to enable or disable the providing of the
debug information. In one form a single bit functions as the mechanism
for each correlated register. Debug operations including breakpoints,
tracing, watchpoints, halting, event counting and others are qualified to
enhance system debug. The registers may be included in a programmer's
model and can be compliant with one or more industry debug related
standards.