ARM ARM1176JZF-S Technical Reference Manual page 437

9.4.3 Processor reset
9.4.4 DBGTAP reset
9.4.5 Normal operation
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A processor or warm reset initializes the majority of the ARM1176JZF-S processor, excluding
the ARM1176JZF-S DBGTAP controller and the EmbeddedICE-RT logic. Processor reset is
typically used for resetting a system that has been operating for some time, for example,
watchdog reset.
Because the nRESETIN signal is synchronized within the processor, you do not have to
synchronize this signal.
DBGTAP reset initializes the state of the processor DBGTAP controller. DBGTAP reset is
typically used by the RealView ICE module for hot connection of a debugger to a system.
DBGTAP reset enables initialization of the DBGTAP controller without affecting the normal
operation of the processor.
Because the DBGnTRST signal is synchronized within the processor, you do not have to
synchronize this signal.
During normal operation, neither processor reset nor power-on reset is asserted. If the DBGTAP
port is not being used, the value of DBGnTRST does not matter.
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Clocking and Resets
9-11