9.1.3. ETB status ports

The ETB continuously captures and writes data into RAM when trace capture is enabled and either:

A trigger event is denoted when the trigger counter reaches zero, or if the trigger counter is zero when the trigger input is HIGH.

When the trigger counter reaches zero the acquisition complete flag, AcqComp, is activated and trace capture stops. The value loaded into the trigger counter therefore sets the number of data words stored in the trace RAM after a trigger event.

Table 9.2 shows the ETB status ports.

Table 9.2. ETB status ports

NameTypeDescription
ACQCOMPOutputWhen HIGH, indicates that trace acquisition is complete, that is, the trigger counter is at zero.
FULLOutputWhen HIGH indicates that the ETB RAM has overflowed or wrapped around to address zero.

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