2.2.4. Trace links

Links provide connection, triggering, and flow of traced data. The following sections describe the links:

Trace funnel

The Trace funnel combines up to eight trace sources on a single funnel. A static arbitration scheme selects the input trace stream to pass at any instant. The static arbitration permits reorganization of the slave port priorities between trace sessions. You can chain funnels together, with the ATB output from one funnel connected to an ATB input port of another. This enables you to both increase the number of inputs, and to connect independent systems together.


The Replicator enables you to wire two trace sinks together and operate them on the same incoming trace stream. The input trace stream is output on two ATB ports that can then operate independently.

Synchronous 1:1 ATB Bridge

The Synchronous ATB Bridge provides a register slice that enables timing closure through the addition of a pipeline stage. It also provides a unidirectional link between two synchronous ATB domains. The bridge is 1:1 because both the input and output interfaces exist in the same clock domain. Because the bridge is a single register slice over the ATB interface, it temporarily holds one cycle of trace data within the register bank.

Embedded Trace FIFO (ETF)

The Embedded Trace FIFO is a trace buffer that uses a dedicated SRAM as either a circular capture buffer, or as a FIFO. The trace stream is captured by an ATB input that can then be output over an ATB output or the Debug APB interface.

The ETF is a configuration option of the Trace Memory Controller (TMC).

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