12.4. Debug register descriptions

Table 12.9 shows definitions of terms used in the register descriptions.

Table 12.9. Terms used in register descriptions

TermDescription
R

Read-only. Written values are ignored.

W

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

RWRead or write.
RAZRead-As-Zero (RAZ). Return a value of zero when read.
SBZShould-Be-Zero (SBZ). Should be written as zero (or all 0s for bit fields) by software. Non-zero values might produce Unpredictable results.
SBZPShould-Be-Zero or Preserved (SBZP). Should be written as zero (or all 0s for bit fields) or preserved by writing the same value that has been previously read from the same fields on the same processor.
UNPA read of this bit returns an Unpredictable value.

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