7
1-5-3. Media directory structures
The directory structure of each medium is as follows.
Root directory
VR-24_DATA
*1
Aaaaaaaa0001.dat
*2
Aaaaaaaa0001.hdr
*2
Aaaaaaaa0001.wav
*2
*3
Aaaaaaaa0001_C1.avi
*2
*3
Aaaaaaaa0001_C2.avi
*2
*3
1 VR-24_DATA
This directory is made automatically when
the medium is formatted. When the medium
is inserted in an VR-24, this directory is made
automatically if it does not already exist.
2 These files are created for each ID.
3 These are created when recorded.
1-5-4. Data file
16-bit data converted from analog to digital is recorded
as 2-byte integer values from −32768 to +32767 while
24-bit converted data is recorded as 4-byte integer val-
ues from −8388608 to +8388607. Negative numbers are
shown using two’s-complement notation.
The byte order is from the lowest to the highest (Intel
format).
The data order is from the first sampling channel to
the second sampling channel and so on until the last
sampling channel. This order is called the INTERLACED
format, and the format name is recorded in STORAGE_
MODE in the header file.
The structure of a data file is as follows. In this docu-
ment, a collection of data as shown in the example is
called a “scan”. A data file is made of repeated scans.
Example of data for one scan recorded at 6 kHz sampling
frequency
Data order
CH1
CH2
1/6000
CH3
CH4
1-5-5. Converting data to physical
quantities
16-bit data converted from analog to digital is recorded
as integer values from −32768 to +32767 and the value
would be ±25000 when the input is ±100% in the input
range settings. 24-bit converted data is recorded as inte-
ger values from −8388608 to +8388607 and the value
would be ±6400000 when the input is ±100% in the
input range settings. The input value is obtained from
the following formula:
Input value = (A/D conversion value of the data file) ×
SLOPE + Y_OFFSET
o
See “Explanations of header file” on page 9 for
information about SLOPE and Y_OFFSET.
1. Introduction
Summary of Contents for VR-24
Page 1: ...Analog Visual Recorder Owner s Manual Z VR 24 D01255010D...
Page 67: ...67 15 Exterior drawings 260 77 12 5 186 Unit mm...
Page 70: ...70...
Page 71: ...71...
