3.7.1. EmbeddedICE watchpoint comparator input behavior

If you can control the behavior of the EmbeddedICE watchpoint comparator inputs, and specify different behavior of these inputs in different contexts, these signals are more useful for controlling tracing.

For example, if you are controlling the TraceEnable event, you want the controlling input held between comparisons, so that TraceEnable is active through a range of addresses.

In contrast, if you want to use an EmbeddedICE watchpoint comparator input as an input to the trace start/stop block, it is preferable if the input is pulsed for a single cycle. This avoids the possibility, for example, that a stop signal might be missed because a start signal from an EmbeddedICE watchpoint comparator input is still asserted.

To take account of these different requirements, if the EmbeddedICE Behavior Control Register is implemented, a debugger can program this register to select the default behavior of each EmbeddedICE watchpoint comparator input as either pulsed or latched, depending on the required use of each input. For more information see EmbeddedICE Behavior Control Register, ETMEIBCR.

If the EmbeddedICE Behavior Control Register is not implemented then the behavior of the EmbeddedICE watchpoint comparator inputs differs for different resources. See Default behavior of EmbeddedICE watchpoint comparator inputs.

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