MRU
Demo Program Manual
Inertial Labs, Inc
TM
Address:
39959 Catoctin Ridge Street, Paeonian Springs, VA 20129 U.S.A.
Tel: +1 (703) 880-4222, Fax: +1 (703) 935-8377
Website:
www.inertiallabs.com
102
APPENDIX C.
Description of data files
The Inertial Labs MRU Demo software creates data files if “
Write
” button is
pressed after MRU start. These are two binary files with the same name and
extensions .prm and .bin, where .prm file contains the MRU parameters, and
.bin file contains the MRU outputs. Select «
Report of experiment
» from the
“Convert
“ menu
of
the MRU Demo or press F8 or click
button to convert
these binary data to text file (see section 7 for more details).
Structure of binary and text files is described below. Note that text file is
more convenient for analysis.
C.1. Structure of binary file
If user has possibility to work with binary file directly, below is description of
the binary .bin file. This file structure copies structure of the MRU output
data that is described in the Inertial Labs MRU Interface Control Document
(ICD).
The first 50 bytes of the *.bin file are results of the MRU initial alignment, see
Table C.1.
Table C.1. Structure of the first 50 bytes of *.bin file (block of initial alignment data)
Byte
Parameter
Format Length
Note
0-11
Gyros
bias
float
3*4
3 numbers in ADC codes
12-23 Average acceleration
float
3*4
3 numbers in ADC codes
24-35 Average magn. field
float
3*4
3 numbers in ADC codes
36-39 Initial Heading
float
4
degrees
40-43 Initial Roll
float
4
degrees
44-47 Initial Pitch
float
4
degrees
48-49 USW
word
2
0 – successful initial alignment;
0 – unsuccessful
Notes:
1.
USW is Unit Status Word (see Appendix D. The Unit Status Word definition, for
details).
2.
In the Table C.1 and in all next there is denoted:
word = unsigned 2 byte integer;
sword = signed 2 byte integer.