12.4. Debug register descriptions

Table 12.5 shows definitions of terms used in the register descriptions.

Table 12.5. Terms used in register descriptions


Read-only. Written values are ignored.


Write-only. This bit cannot be read. Reads return an Unpredictable value.

RWRead or write.
RAZRead-As-Zero. Always zero when read.
RAORead-As-One. Always one when read.

Should-Be-Zero (SBZ) or Preserved (P). Must be written as 0 or preserved by writing the same value previously read from the same fields on the same processor. These bits are usually reserved for future expansion.

UNPA read from this bit returns an Unpredictable value.

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