7.11.3. FIFO draining

When there is no trace to output then TRACECTL and TRACEDATA[0] are both asserted. During any cycle in which trace is output, TRACECTL is deasserted.

Usually no trace is output unless there is sufficient trace to fill the entire width of TRACEDATA. This makes the most efficient use of the space in the TCD where TRACEDATA is wider than 8 bits.

If trace is output when there is not sufficient trace to fill TRACEDATA then Ignore headers are output on the unused upper bytes. The circumstances where this is permitted are:

During Trace Disabled, TRACEDATA[1] must also be asserted. This is ignored by the TPA.

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