RealView Debugger Trace User Guide: 4.3.2. Trace port mode (ETMv1)

4.3.2. Trace port mode (ETMv1)

This control specifies the way the trace port operates. For ETMv1 architectures, select one of the following values:

Normal: The normal mode. Trace data from the ETM is written to the output pins at the processor frequency.
Multiplexed: Use this to reduce the number of output pins used by the trace port. Two output signals are output on the same pin by clocking the signals at double the normal rate.
De-Multiplexed: Use this to reduce the signal switching frequency of the trace port signals. One output signal is output on two pins, so the pins are clocked at half the normal rate.

Note

Only Normal mode operation is possible when you are using ETM hardware implementing ETM Architecture version 1.1 or earlier.
If you use multiplexed or demultiplexed clocks, you might have to alter the configuration of your TPA.

You can also use this section of the dialog box to enable or disable half-rate clocking, or suppress output from the trace port:

Half-rate clocking enabled

Select Half-rate clocking enabled if you want to set the ETM half-rate clocking signal. The effect of this signal is dependent on the implementation of your system.

Note

This setting is not available when you are using ETM hardware implementing ETMv1.0. Hardware implementing ETMv1.1 might support the setting, but RealView Debugger cannot detect whether it does.
If you enable half-rate clocking, you might have to alter the configuration of your TPA.
This capability is not supported by all TPA. See the documentation that accompanies your hardware to see if it is available.

Disable traceport

Select Disable traceport if you want to suppress the output from the trace port. This is useful if your hardware has two or more ETMs sharing a single trace port.

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