1.1.1. Structure of a PTM

The main features of a PTM are:

Trace generation

Outputs information that helps you to understand the operation of the processor. The trace protocol provides a real-time trace capability for processors that are deeply embedded in much larger ASIC designs.


You cannot determine how the processor is operating internally by observing the pins of the ASIC, because the ASIC typically includes significant amounts of on-chip memory.

Triggering and filtering facilities

The PFT architecture specification defines a range of triggering and filtering resources that can be used to control tracing. For a number of these, it is implementation defined:

  • whether a PTM implementation includes the resource

  • how many instances of the resource are included.

If you are designing a PTM you can specify the exact set of triggering and filtering resources required by your particular application.

Resources include address comparators, counters, and sequencers.

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