3.11.6. ETB Trigger Counter register

The TRG register characteristics are:


Stops the formatter after a defined number of words are stored following the trigger event and disables write access to the trace RAM. The number of 32-bit words written to the trace RAM following the trigger event is equal to the value stored in this register plus 1.

Usage constraints

There are no usage constraints.


This register is available in all configurations.


See the register summary in Table 3.79.

Figure 3.78 shows the bit assignments.

Figure 3.78. TRG register bit assignments

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Table 3.85 shows the bit assignments.

Table 3.85. TRG register bit assignments




The counter is used as follows:

Trace after

The counter is set to a large value, slightly less than the number of entries in the RAM.

Trace before

The counter is set to a small value.

Trace about

The counter is set to half the depth of the trace RAM.

You must not write to this register when trace capture is enabled, FFSR.FtStopped is 0, and CTL.TraceCaptEn is 1. When a write is attempted, then the register is not updated. A read operation is permitted when trace capture is enabled.

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