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Chronology from Joe Skapik and John Fitch:

10/25/94

FOS 94297 Safing Event

94.297:05:51:28 Low Voltage Enabled

05:57:02 Processor initialization completed - OK
All telemetry nominal.

05:59:32 High Voltage relay closed
No indication of micro-processor reset.

06:00:15 Speed Check equals zero. This was first sample
after high voltage turn on began.

06:02:22 Housekeeping enabled

06:03:24 Speed Check Error counter increments to one.

06:04:01 - 06:05:49
High Voltage ramp up nominal.

06:04:18 Stat buff error 3023 - initial Speed Check Error.

06:06:18 - 06:38:18
Stat buff error 3024 - Speed Check Error issued
every 2 minutes. Speed Check remains zero,
Speed Check Error counter incrementing once
per major frame.

06:37:20 Began commanding for FOS observation.

06:37:54 Shutter commanded to open. Remained closed.

06:38:33 UDL dump commanded.

06:39:01 Watchdog timer error.
Keep Alive counter equals zero.
Firmware Version Number equals zero.

06:39:02 Error Check counter equals zero.

06:39:03 Stat buff error 3013 - Keep Alive error.

06:39:16 Self Check equals zero.

06:39:18 Stat buff error 3029/3 - Self Check error

06:39:33 Stat buff error 3033 - Firmware Version test error

06:39:28 Stat buff error 3041 - Error Check error

06:40:03 Stat buff error 3014 - Second Keep Alive error

06:40:03 Exec 323 - FOS Safing Processor initialized.


Priority of FOS Firmware Interrupts:

Reset
Telemetry frame sync
Terminate immediately
Stop data collection
Accumulator close
Accumulator open
Start data collection
Serial magnitude command
SDF buffer empty
background tasks


Al Holm's Notes from the 12:00 meeting:

- At the first readout after the high voltage relay
was closed, the Speed Check parameter went to zero.
(My interpretation of what was discussed is that
the microProcessor was not servicing the background
task commands.) The HV relay was closed at 05:59:32.

- Following this the microProcessor continued to
process serial commands correctly. This is indicated
by a nominal HV ramp up from 06:04:01 to 06:05:49.

- Starting at 06:04:18 and then at 2 minute intervals,
the status buffer messages were issued to report
the Speed Check Error. These intervals are set by
the software.

- At 06:37:54 the shutter was commanded to open, but
it remained closed. Shutter opening is a background
task, so this is consistent with the continuing
Speed Check Errors.

- At 06:38:33 the UDL dump was commanded but did not
start. (No one mentioned whether this also is a
background task.)

- At 06:39:01 the microProcessor essentially stopped.
There was a watchdog timer error, the Keep Alive
Counter went to zero, and the Firmware Version
Number went to zero.

- At 06:39:03 and, one minute later, at 06:40:03
status buffer messages reported the Keep Alive
Error. When the second status buffer message was
issued, the safing processor was initiated.

- That's all, folks. There is no understanding of why
all this occurred. The betting ($0.05 by Dana
Mitchell and $0.10 by John Fitch) is that this was
a transient event and that the blue-side microProcessor
will work fine when it is reset.