Cheryl, Fil, Dave:

At around 23:06 PDT Mon 3rd September h1susex had a significant timing glitch which caused the IOP model to lose track of DAC channels, triggering it to enter its safe mode whereby it does not drive any DAC channels. This is indicated by the DACKILL (DK) bit being set on the stateword, and each 18bit DAC having bit 4 (right-most bit) set to red indicating the AI chassis have been remotely turned off.

We made a note of the SDF differences (h1susetmx=72, h1sustmsx=8, h1susetmxpi=0) and restarted the models. Fil was at EX and verified the AI chassis were operating correctly.

We "burt restored" using the SDF EDB-load back to the settings captured during shutdown of the user models, and now have the original number of differences in the SDF.