Description: The table of announcements is used to provide a common interface to varied mechanisms for announcing conditions. Each announcement in an Annunciator's current set contains a severity level, details describing the specific condition that is being reported, an Acknowledged flag, a timestamp indicating when the announcement was added to the set, and an EntryId that uniquely identifies the particular status item within the set. EntryIds are assigned to announcements as they are added to the set as well as a Timestamp. After an announcement is deleted from the current set, its EntryId may be reused for a newly added announcement as long as the new announcement will have a different timestamp than any previously deleted announcement using the same EntryId. Thus, the EntryId and Timestamp together will uniquely identify any announcement, which was ever present in the Annunciator's set.

The actual meaning of the Acknowledged flag is arbitrary, and the actions taken by the platform when announcements are flagged as 'acknowledged' or 'unacknowledged' are implementation-specific. The intended use of the flag is to indicate whether a particular announcement in the current set has been recognized by whomever or whatever is inspecting the LEDs, displays, etc., that are being driven by the Annunciator management instrument. Thus, when announcements are added to the current set, generally the flag should be set to indicate that the condition is 'unacknowledged'. Later, either as the result of an HPI User function call, or due to some implementation-dependent action (such as pressing an 'acknowledge' button on a front-panel display), the flag can be changed to indicate that the announcement is now 'acknowledged.'

The ability to acknowledge announcements is not controlled by the Annunciator 'mode' setting (Auto, User, or Shared). Any announcement may be acknowledged by the HPI implementation, or via the hpiAnnunciatorAcknowledge() function call, regardless of the current mode setting for the Annunciator.

Over time, announcements are added to and deleted from an Annunciator`s current set of announcements. This may be done automatically by the HPI implementation to reflect platform fault conditions, or by the HPI User via the HPI interface. When announcements are added or deleted automatically by the HPI implementation, it is implementation-specific which announcements are added or removed.