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Comment: Migrated to Confluence 5.3

The plot of GPSdiff_max for May 22, 2011 shows a maximum value of around 25 seconds between 11:05 and 17:00 UTC, indicating something went haywire with the data collection during those times.

Looking at the downloaded data, it appears that data stopped coming in on the Diamond serial ports at 11:05, and resumed at 17:00. There is not a large gap in data from the 3 sensors that are sampled on the Viper serial ports, but they show large time tag delta-Ts, followed by many small delta-Ts, symptomatic of the system getting behind and having to do major buffering. Perhaps a "storm" of interrupts from the Diamond that finally cleared up? Moisture somewhere?

I don't have time to look into it at this time, but here are some dumps of data around the problem.

Code Block
data_stats /scr/isfs/projects/BEACHON_SRM/raw_data/manitou_20110522_000000.dat
2011-05-24,16:56:30|INFO|opening: /scr/isfs/projects/BEACHON_SRM/raw_data/manitou_20110522_000000.dat
EOFException: /scr/isfs/projects/BEACHON_SRM/raw_data/manitou_20110522_000000.dat: open: EOF
sensor  dsm sampid    nsamps |------- start -------|  |------ end -----|    rate minMaxDT(sec) minMaxLen
          1     20     39901 2011 05 22 00:00:00.998  05 22 11:05:01.461    1.00  0.336  1.643   19   19
          1     30     84632 2011 05 22 00:00:00.571  05 22 11:59:59.719    1.96  0.042 26.076   51   73
          1    100    843525 2011 05 22 00:00:00.160  05 22 11:59:59.944   19.53 -2.052 27.951   12   16
          1    110    415176 2011 05 22 00:00:00.113  05 22 11:59:59.959    9.61 -2.016 28.058   39   87
          1    120     41042 2011 05 22 00:00:00.185  05 22 11:05:01.388    1.03  0.294  1.643   29   31
          1    200    798028 2011 05 22 00:00:00.166  05 22 11:05:01.873   20.00  0.005  0.596   12   12
          1    220     40687 2011 05 22 00:00:00.791  05 22 11:05:01.158    1.02  0.357  1.604   28   29
          1    300    798048 2011 05 22 00:00:00.168  05 22 11:05:01.884   20.00  0.002  0.585   12   12
          1    310    399023 2011 05 22 00:00:00.000  05 22 11:05:01.841   10.00  0.042  0.454   44   49
          1    320     40488 2011 05 22 00:00:00.233  05 22 11:05:01.428    1.01  0.356  1.613   28   29
          1    330      7981 2011 05 21 23:59:55.213  05 22 11:04:55.250    0.20  4.415  5.586   49   60
          1    400    798041 2011 05 22 00:00:00.005  05 22 11:05:01.883   20.00  0.001  0.591   12   12
          1    420     40772 2011 05 22 00:00:00.328  05 22 11:05:01.192    1.02  0.344  1.614   29   30
          1    500    798042 2011 05 22 00:00:00.171  05 22 11:05:01.913   20.00  0.002  0.603   12   12
          1    510    399020 2011 05 22 00:00:00.007  05 22 11:05:01.814   10.00  0.037  0.436   44   49
          1    520     40747 2011 05 22 00:00:00.342  05 22 11:05:01.149    1.02  0.372  1.588   27   29
[maclean@porter ~]$ data_stats /scr/isfs/projects/BEACHON_SRM/raw_data/manitou_20110522_120000.dat
2011-05-24,16:57:04|INFO|opening: /scr/isfs/projects/BEACHON_SRM/raw_data/manitou_20110522_120000.dat
EOFException: /scr/isfs/projects/BEACHON_SRM/raw_data/manitou_20110522_120000.dat: open: EOF
sensor  dsm sampid    nsamps |------- start -------|  |------ end -----|    rate    minMaxDT(sec) minMaxLen
          1     20     25156 2011 05 22 17:00:47.215  05 22 23:59:59.960    1.00  0.019     1.371   19   29
          1     30     73288 2011 05 22 12:00:25.745  05 22 23:59:59.741    1.70  0.104    26.116   51   73
          1    100    750227 2011 05 22 12:00:28.065  05 22 23:59:59.959   17.38 -2.052    27.951   12   16
          1    110    337790 2011 05 22 12:00:28.120  05 22 23:59:59.922    7.82 -2.016    28.058   17   69
          1    120     25895 2011 05 22 17:00:47.289  05 22 23:59:59.553    1.03  0.029     1.756   29   38
          1    200    502634 2011 05 22 17:01:05.737  05 22 23:59:59.999   20.00  0.000     2.518    2  466
          1    220     25715 2011 05 22 17:00:47.290  05 22 23:59:59.392    1.02  0.028     1.594   28   39
          1    300    502351 2011 05 22 17:01:20.419  05 22 23:59:59.968   20.00  0.000     2.538    2  465
          1    310    251531 2011 05 22 17:00:47.284  05 22 23:59:59.926   10.00  0.050     0.154   44   66
          1    320     25590 2011 05 22 17:00:47.291  05 22 23:59:59.734    1.02  0.028     1.315   28   39
          1    330      5032 2011 05 22 11:05:00.251  05 22 23:59:50.264    0.11  0.061 21347.049    6   61
          1    400    502055 2011 05 22 17:01:35.059  05 22 23:59:59.987   20.00  0.001     2.508    3  466
          1    420     25769 2011 05 22 17:00:47.292  05 22 23:59:59.864    1.02  0.029     1.523   29   37
          1    500    502936 2011 05 22 17:00:45.341  05 22 23:59:59.998   19.99  0.003     4.123   12  466
          1    510    251530 2011 05 22 11:05:01.916  05 22 23:59:59.963    5.41  0.027 21345.401   43   50
          1    520     25730 2011 05 22 17:00:47.294  05 22 23:59:59.423    1.02  0.028     1.631   26   39

Data kept coming in on the Viper serial ports (ids=30,100,110, GPS, sonic and licor at 2m), but had time tag issues, apparently because buffers filled up. Here's a snippet of the 2m sonic data in hex, showing a 28 second time tag jump, but no skip in the sonic sequence (byte 9: f8,f9,fa,fb,fc, etc)

Code Block
2011 05 22 11:05:53.8243 0.05004      12 20 06 0b 03 39 ff 6e e8 f5 0f 55 aa
2011 05 22 11:05:53.8743 0.04997      12 6a 06 0f 03 1b ff 6a e8 f6 0f 55 aa
2011 05 22 11:05:53.9243 0.05002      12 bf 05 b1 02 de fe 69 e8 f7 0f 55 aa
2011 05 22 11:05:53.9743 0.04998      12 4d 05 cb 02 d0 fe 6e e8 f8 0f 55 aa
2011 05 22 11:06:21.9147   27.94      12 35 05 d6 02 df fe 71 e8 f9 0f 55 aa
2011 05 22 11:06:21.9272  0.0125      12 03 06 7f 03 30 ff 6f e8 fa 0f 55 aa
2011 05 22 11:06:21.9397  0.0125      12 32 06 7f 03 98 ff 65 e8 fb 0f 55 aa
2011 05 22 11:06:21.9522  0.0125      12 46 05 59 02 35 ff 6d e8 fc 0f 55 aa
2011 05 22 11:06:21.9647  0.0125      12 83 05 1a 03 c3 fe 75 e8 fd 0f 55 aa

After the gap, the 0.0125 dTs result from unpacking multiple samples from a buffer, where the code computes a dT = 10 bits/byte / (9600 bits/sec) * 12 bytes/sample = 0.0125 sec/sample

I see no indication of a problem in the system logs, or any weird clock adjustments in the NTP loopstats,peerstats.