8.6.2. Current Port Size Register, 0x004

This register is read/write. The Current Port Size Register has the same format as the Supported Port Sizes register but only one bit is set, and all others must be zero. Writing values with more than one bit set or setting a bit that is not indicated as supported is not supported and causes unpredictable behavior.

On reset this defaults to the smallest possible port size, 1 bit, and so reads as 0x00000001.


Do not modify the value while the Trace Port is still active, or without correctly stopping the formatter (see Formatter and Flush Control Register, 0x304). This can result in data not being aligned to the port width. For example, data on an 8-bit Trace Port might not be byte aligned.

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