SrdoInvalidReason Enum¶
Why an SRDO is not valid (CiA DSP 304 V1.0 §8.1.1, §8.1.3.1, §9.5).
Fields¶
NotReceived 0
Consumer: no complete pair since entering Operational.
NotOperational 1
The node is not in NMT state Operational; SRDOs exist only there (§8.3.2).
ConfigurationInvalid 2
13FEh is not A5h, or 13FFh does not match the record (§8.3.1 D, §9.5).
SafeguardCycleExpired 3
Consumer: no valid pair within the SCT (§8.1.1 Figure 2).
ValidationTimeExpired 4
Consumer: the second frame did not follow the first within the SRVT (§8.1.1 Figure 3).
OutOfOrder 5
Consumer: the inverted frame arrived without a preceding plain frame (§9.5).
Mismatch 6
Consumer: the second frame is not the bitwise inverse of the first (§8.1, §9.5), or a frame on either id is not a classic CAN frame — a CAN FD frame, or more than 8 bytes.
ActuationRefused 7
Consumer: a complete pair arrived, but a mapped object refused the bytes meant
for it (a write validator, or a declaration that no longer takes them). Data the
consumer cannot use counts as not received, as §8.1.3.1 leaves a pair too short for the
mapping unprocessed: SrdoReceived is not raised and the SCT
is not restarted. The reason is the most recent cause: an SCT still running keeps running
from the last pair that was taken, and its expiry reports
SafeguardCycleExpired; an SCT that had expired before this pair stays
expired, and this reason replaces that one.
The writing stops at the refusal: the objects mapped before it keep the bytes of this
pair, the refused one and those after it keep their previous values. The refusal is
reported on BackgroundExceptionOccurred. The next pair the objects take makes the
SRDO valid again. On a node this is a safeguard, like MappedObjectUnavailable:
no public path produces a refused mapped write today — the node installs no write
validator on application objects and offers no public one, and it refuses to re-declare an
object an existing SRDO maps.
MappedObjectUnavailable 8
Producer: a mapped object is missing, has no fixed width, or no longer has the
width its mapping entry gives it (§8.1.3.1: the SRDO carries its mapped objects at that
length; an SRDO maps fixed-width objects only, this implementation's rule). The
producer transmits nothing — no pair is padded or cut to fit — and stays silent until the
SRDO is rebuilt (a record written, or Operational entered again); the failure is
reported on BackgroundExceptionOccurred. A node refuses to re-declare an object an
existing SRDO maps, so this is the guard behind that rule, not a way to reach it.