Box: 482 Box: 429
Address: 51c0000 51d0000 Address: 50c0000 50d0000
Index: 209 333 Index: 209 333
Time: 2013.76 2042.98 Time: 2013.76 2042.98
Ped: 26 25 Ped: 26 25
Min: -2236.38 -5008.66 Min: -2236.38 -5008.66
Moment: 1159.75 2184.97 Moment: 1159.75 2184.97
>1 dBit: 0.08 >1 dBit: 0.08
Status: OK Status: OK
Hit by track Hit by track
Position in Box: 326.34 Position in Box: 304.51
netDiffCor: -22.16 netDiffCor: -12.18
(the final two numbers are different because of calibrations). To
make sure that Chris, for whom I have rispetto profundo, had not
screwed it up in the postprocessing, I went all the way back to the
zebra DLT and saw that the data in the original waveform equipment is
the same (sort of):
ID=1 record, equipment 6042 | ID=2 record, equipment 6042
050D 0000 | 0000 051D
0000 047E 0000 1A1A | 047E 0000 1A1A 0000
1B19 0000 0490 1B1A | 0000 1B19 1B1A 0490
1B19 0000 FFB7 191C | 0000 1B19 191C FFB7
191B 8888 FFB3 1D1E | 8888 191B 1D1E FFB3
1B1D 8888 FFAF 1F1F | 8888 1B1D 1F1F FFAF
... | ...
It looks like my DREAM event dumper is doing something weird with the
byte ordering of the 32-bit words, but the data is essentially the
same.
This seemed to have happened a lot on SM5, perhaps confined to runs
11464-11482. I thought I saw an example last night on SM2 as well,
but I haven't been able to find it again.
This could happen if the VME crate did not understand which channel it
was asked to read out. Conceivably it could also happen on the
microvax if it read a buffer full of data and passed it to the
acquisition program, then read another buffer and somehow passed the
pointer to the old data to the ACQ.
A second example is 11470 499, channels 520/521 and 500/501. Note
that in both events the VME addresses differed by only one bit, but
they were different bits in the two cases.
Needless to say, relying on the waveform data from one channel to
compute the timing for a different box leads to unsatisfactory
results.
Bob