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The following table lists the ATB Trace interface signals that are intended to connect to an external TPIU.
This trace interface is synchronous to DEBUGFCLK, is reset using nPORESETDEBUG, and resides in the PD_DEBUG power domain.
Table A-11 Trace signals
|Signal name||Width||Direction||Clock domain||Description|
|ATVALID||1||Output||DEBUGFCLK||A transfer is valid during this cycle. If LOW, all the other ATB signals must be ignored in this cycle.|
|ATID||7||Output||DEBUGFCLK||An ID that uniquely identifies the source of the trace.|
|ATBYTE||1||Output||DEBUGFCLK||The number of bytes on ATDATA to be captured, minus 1.|
|ATDATA||16||Output||DEBUGFCLK||Trace data bus.|
|ATREADY||1||Input||DEBUGFCLK||Slave is ready to accept data.|
|AFVALID||1||Input||DEBUGFCLK||This is the flush signal. All buffers must be flushed because trace capture is about to stop.|
|AFREADY||1||Output||DEBUGFCLK||This is a flush acknowledge. Asserted when buffers are flushed.|
|SYNCREQ||1||Input||DEBUGFCLK||Trace synchronization request trace sinks|