6.4.1. Use of the event bus and counters

The event bus is designed to be connected to the ETM-R5, that enables processor events to trigger tracing for debug purposes. You can also connect it to event counting registers external to the processor, or to an interrupt generator.

Because each EVNTBUSm pin is only asserted for one cycle for each occurrence of the event, it is possible to create composite events by ORing various EVNTBUSm pins together. A composite event signal like this is asserted when any of the included events occur although, if multiple events occur in the same cycle, the composite event only occurs once.

The processor also has two event input pins, ETMEXTOUTm[1:0]. This bus is normally intended for connection to the ETM, and enables the Cortex-R5 performance monitor to count events generated by the ETM. These inputs can alternatively be used for composite events generated external to the processor.

Copyright © 2010-2011 ARM. All rights reserved.ARM DDI 0460C