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Disabled slow updates, but didn't help with 100% dead time.  Do blowoff (to empty queues) and clear readout (to clear latched XpmOverflow which in turn latches deadtime?).  Then pgpread sees transitions and some l1accepts (although haltingly?) before deadtime kicks in.

Tried the FifoReset here in addition to blowoff and clearreadout but don't see any l1accepts in pgpread:

Image Added

Not Understood Failure Modes

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