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nication; plus, the Frame Change transitions between them. The following is a brief
textual description of each frame.
1. The Hardware Initialization (HW Init) frame follows Arinc 659’s definition for
the Initialization frame and, as such, is an Unversioned frame. The only data
traffic during the HW Init frame is the transfer of Version Messages from all
LRMs. The HW Init frame is approximately 117 microseconds in duration.
2. The Software Initialization (SW Init) frame provides time for the processors’
environment to be setup before the functional partitions are dispatched in the
Flight frame.
3. The Built in Test (BIT) frame is a Versioned frame that provides time to per-
form power-up BITE.
4. The Flight frame is a Versioned frame that provides ...