13.3.3. Formatter and Flush Control Register

The TPIU_FFCR characteristics are:


Controls the TPIU formatter.

Usage constraints

There are no usage constraints.


Available in all configurations.


Figure 13.4 shows the TPIU_FFCR bit assignments.

Figure 13.4. TPIU_FFCR bit assignments

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Table 13.4 shows the TPIU_FFCR bit assignments.

Table 13.4. TPIU_FFCR bit assignments


This bit Reads-As-One (RAO), specifying that triggers are inserted when a trigger pin is asserted.


Enable continuous formatting. Value can be:


Continuous formatting disabled.


Continuous formatting enabled.


The TPIU can output trace data in a Serial Wire Output (SWO) format. See Serial Wire Output format.

When one of the two SWO modes is selected, bit[1] of TPIU_FFCR enables the formatter to be bypassed. If the formatter is bypassed, only the ITM and DWT trace source passes through. The TPIU accepts and discards data from the ETM. You can use this function to connect a device containing an ETM to a trace capture device that is only able to capture SWO data. Enabling or disabling the formatter causes momentary data corruption.


If TPIU_SPPR is set to select Trace Port Mode, the formatter is automatically enabled. If you then select one of the SWO modes, TPIU_FFCR reverts to its previously programed value.

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