Tags:
create new tag
view all tags

July 2006 CDS Report (Error Messages & Efficiency)

Filter Usage

  Time (s) Cathode Time (%) Cathode
Num Description Pos Used Down Up Down Up
0 Blocked 2200 0 0.0 0.0 0.00 0.00
0 Blocked 0000 349 527485.5 30729.6 19.70 1.15
1 UV Grism Clocked 0160 28 3973.0 13500.2 0.15 0.50
1 UV Grism 0200 0 0.0 0.0 0.00 0.00
2 UVW2 0400 1386 16034.5 453171.9 0.60 16.92
3 V 0600 877 25480.3 134844.4 0.95 5.04
4 UVM2 0800 1336 106207.0 390092.7 3.97 14.57
5 Vis Grism Clocked 0955 17 183.3 6263.3 0.01 0.23
5 Vis Grism 1000 0 0.0 0.0 0.00 0.00
6 UVW1 1200 1521 88968.4 306408.4 3.32 11.44
7 U 1400 1720 37369.7 308266.9 1.40 11.51
8 Mag 1600 0 0.0 0.0 0.00 0.00
9 B 1800 841 4512.5 98572.1 0.17 3.68
10 White 2000 180 6059.7 119985.1 0.23 4.48
  Totals   8255 816274.0 1861834.6 30.48 69.52

Observing Efficiency

Description Time (s) % Time
UNKNOWN 8192.68 0.31
BASIC 219.16 0.01
SAFE 73569.76 2.75
SLEW 311424.20 11.63
SETTLING 89.33 0.00
FINDING 897.13 0.03
AUTOMATED 83406.76 3.11
PLANNED UNBLOCKED 1754614.54 65.51
PLANNED BLOCKED CATHODE DOWN 44683.49 1.67
PLANNED BLOCKED CATHODE UP 30456.95 1.14
SAFEPOINT 521.46 0.02
SAA UNBLOCKED NON AT 6413.63 0.24
SAA UNBLOCKED AT 10691.80 0.40
SAA BLOCKED 328900.20 12.28
IDLE 23551.49 0.88
UNPLANNED IDLE 485.53 0.02
     
TOTAL 2678337.27 100.0

Comments on Errors

Note: a summary of the NHK messages encountered this month, listed in increasing frequency of occurrence, may be found at http://msslje.mssl.ucl.ac.uk/lists/nhklis_2006-07.txt

SlewAbort

A slew abort alert was received at 11:17:02 UT (SC_EVENT:FOMINFO - FOM SLEW ABORT 2006-184-11:17:02). This is because the spacecraft did not receive an "OK to slew" message from UVOT. UVOT did send such a message but the s/c could not read it. The UVOT ICU TC Reject Counter therefore incremented from 5 to 6. This problem has been seen before and is being monitored/tracked via S-Swift-0074. The ICU errors counter was therefore reset and a new SOARS anomoly report was raised (S-0413).

DPU Unexpected ACK/NAK

This message heralded a major problem with the DPU. The DPU locked up at 2006-07-20 22:30:03.48 UT (i.e. failed to respond to ICU commands). It was commanded to send TDRSS HK, and it did not respond. It was agreed to put the ICU in SAFE and wait till morning to come up with a plan to power cycle the DEM.

Initial diagnosis from Scott Koch: It looks like a semaphore timed out, then SCUI hung for a while. During that interval, the command queue overran, and the DPU was not able to recover from that as it will not accept further commands.

Illegal APID

At 2006-07-21T17:38:53.01 during the last DEM power on, we got an Illegal APID 0000 0000 TC APID=66a FC=37 6a0037 Pkt 2006-07-21 17:38:53.01 \/U

This was caused by the telecommand

/D_HK_P_CPY_TDRSS CTRL=ENABLE

which is sent to the DPU via the ICU so is actually an ICU telecommand (so it ought to really begin with an "I" instead of a "D").

The intention was to turn on the DPU TDRSS HK at this point with the ICU in BASIC and the TM not yet powered.

Both dpu_tdrsshk_on.proc and uvot_power_on.proc use this /D_HK_P_CPY_TDRSS telecommand.

For dpu_tdrsshk_on.proc we must remember that this telecommand doesn't work when the ICU is in basic (like just after power on).

For uvot_power_on.proc we should probably change it a little.

The command should be moved down a little in uvot_power_on.proc to after the ICU is in SAFE and knows about DPU commands.


Last revision: r5 - 2006-09-13 - 13:10:39 - HowardHuckle
Edit | Attach | Watch | Print version | History: r5 < r4 < r3 < r2 < r1 | Backlinks | Raw View | More topic actions
Topic revision: r5 - 2006-09-13 - HowardHuckle
 
This site is powered by the TWiki collaboration platform Powered by PerlCopyright © 2008-2019 by the contributing authors. All material on this collaboration platform is the property of the contributing authors.
Ideas, requests, problems regarding TWiki? Send feedback