Svantek SVAN 971, User Manual

Page: 139 / 220

SVAN 971 User Manual
– Appendixes
139
B.2.1.6. Record with Summary Results
The format of the data frame is as follows:
HS L (optional) D L (optional) HE
where:
HS starting header (1 word)
L length of the block (field is optional and occurs only when b7..b0 in header are set to zero)
D Summary Data:
- Main results (cf. Tab. B.1.17_SLM, B.1.17_DM)
- Statistical levels (optional, cf. Tab. B.1.18)
- 1/1 OCTAVE analysis results (optional, cf. Tab. B.1.19)
- 1/3 OCTAVE analysis results (optional, cf. Tab. B.1.20)
- The results of the statistical analysis in profiles(optional, cf. Tab. B.1.21)
HE ending header (1 word), which differs from the HS only on b11 bit (thanks to it, it is possible
to analyse the recorded file starting from its end)
The HEADER format is as follows:
b15 b14 b13 b12 b11 b10 b9 b8 b7 b6 b5 b4 b3 b2 b1 b0
where:
b15 - 1
b14 - 1
b13 - 0
b12 - 0,
b11 - header type:
0 - HS
1 - HE
b10 - 0
b9 - 1
b8 - 1
b15÷b8 – HS (0xC3), HE (0xCB)
b7÷b0 – length of the block (if zero length of the block is saved in additional word L)
B.2.1.7 Record with audio data
This record exists only in the case when the EVENT RECORDING function is active ( path: Measurement
/ Logging / Event Rec. ). Samples of the signal, taken in the periods
from 1 second to 8 hours, are saved in the blocks. Each block is divided into frames, which are stored in
a file among the logger results. The frame starting block and the frame ending it are marked
with the set b10 and b9 bits in the header of the frame, respectively. It happens in the case of stopping the
recording that the ending frame does not exist.
The format of the data frame is as follows:
HS L S L HE
where:
HS starting header (1 word)
L block length (1 word), expressed in words (4 + (number of samples)*1.5)
S samples of the measured signal (in the case of SVAN 959 each sample is written in three bytes; the
recording starts with the least significant byte)