4.3.3. Operation

To address a particular AP, the DP uses the eight MSBs of its address bus, dapcaddrs[15:2]. The value driven on these address lines is determined by the APSEL[7:0] field in the AP Select register. This register is present on all DP implementations that are compliant with the ARM® Debug Interface Architecture Specification, ADIv5.0 to ADIv5.2.

An access to a master interface that does not exist goes to the default slave, which ignores writes and returns zero on reads.

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