NXP Semiconductors QorIQ LS1012A Reference Manual

27.3.31.3 DiagramBits 31 30 29 28 27 26 25 24 23 22 21 20 19 18 17 16R DIAGWReset u u u u u u u u u u u u u u u uBits 15 14 13 12 11 10 9 8 7 6 5 4 3 2 1 0R ERRWReset u u u u u u u u u u u u u u u u27.3.31.4 FieldsField Function31-16DIAGDiagnosticThis bit contains diagnostic error information for use by diagnostic software in validating correct operationor isolating failure modes.Table 27-7. Diagnostic error informationBit Description31:27 Reserved26 Exchanged (X): When set to 1, this bit indicatesthat a change in device presence has beendetected since the last time this bit was cleared.The means by which the implementationdetermines that the device presence has changedis vendor specific. This bit must always be set to 1anytime a COMINIT signal is received. This bit isreflected in the PxIS[PCS] bit.25 Unknown FIS Type (F): Indicates that one or moreFISes were received by the transport layer withgood CRC, but had a type field that was notrecognized.24 Transport state transition error (T): Indicates thatan error has occurred in the transition from onestate to another within the transport layer since thelast time this bit was cleared.23 Link Sequence Error (S): Indicates that one ormore link state machine error conditions wasencountered. The link layer state machine definesthe conditions under which the link layer detects anerroneous transition.22 Handshake Error (H): Indicates that one or moreR_ERR handshake response was received inresponse to frame transmission. Such errors mayTable continues on the next page...SATA AHCI register descriptionsQorIQ LS1012A Reference Manual, Rev. 1, 01/20181564 NXP Semiconductors