7.10.1. Frequency of synchronization

Each form of synchronization must occur in a specified frequency, that depends on the ETM architecture version:

ETMv3.0

Synchronization must occur every n cycles.

ETMv3.1 and later

Synchronization must occur every n bytes of trace.

Where n is the value of the Synchronization Frequency Register, register 0x078. The implementation might delay synchronization in special cases by up to another n cycles, usually to prevent overflow.

An overflow occurs if periodic synchronization does not occur in a period of twice the synchronization frequency.

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