C3.1 DWT functional
A Reduced DWT contains two comparators (DWT_COMP0 to DWT_COMP1) and a Full DWT contains four comparators (DWT_COMP0 to DWT_COMP3). These comparators support the following features:
- Hardware watchpoint support.
- Hardware trace packet support, only if your implementation includes an ITM.
- CMPMATCH support for ETM/MTB/CTI triggers (only if your implementation
includes an ETM, MTB, or CTI).
- Cycle counter matching support (DWT_COMP0 only).
- Instruction address matching support.
- Data address matching support.
- Data value matching support (DWT_COMP1 only in a reduced DWT, DWT_COMP3 only in a Full
- Linked/limit matching support (DWT_COMP1 and DWT_COMP3 only).
The DWT contains counters for:
- Cycles (CYCCNT).
- Folded Instructions (FOLDCNT).
- Additional cycles required to execute all load or store instructions
- Processor sleep cycles (SLEEPCNT).
- Additional cycles required to execute multi-cycle instructions and
instruction fetch stalls (CPICNT)
- Cycles spent in exception processing (EXCCNT).
You can configure the DWT to generate PC samples at defined
intervals, and to generate interrupt event information.
The DWT provides periodic requests for protocol synchronization
to the ITM and the TPIU, if your implementation includes the Cortex®‑M33