Teac DS Series, Instruction Manual, Page: 53 / 104

DS Series Instruction Manual 2006.12
Page 45
7.7 About Data File
Data format of the DS series complies with TAFFmat generally being used at TEAC digital data
recorders. TAFFmat (an acronym for TEAC Data Acquisition File Format) is a file format
composed of the following:
a data file containing A/D (analog to digital) converted data. The file is in binary format
with the extension “dat”.
a header file containing information such as recording conditions. The file is in text format
with the extension “hdr”.
This document uses the term ID to refer to a collection of data collected from the start of
recording on the DS series until the recording is stopped or paused. For each ID, one data file
and one header file is recorded. The above files share a common file name, to which is
appended an ID number. When a new file name is specified, this ID number becomes 1. Each
time recording starts, this number is incremented by 1.
A/D-converted data is recorded as 2-byte integers from -32768 to +32767. Negative numbers
are expressed as complements of 2. The byte order is from the lower bytes to the higher bytes.
The data order is as follows: first sampling channel order -> second sampling channel order
->...-> last sampling channel order. At the LX series, ADC value +/- 25000 represents +/-
100 % of the input range.
This document uses the term scan to refer to a collection of data resulting from one sampling. A
data file is a collection of scan repetitions.
The DS series records the data with 2 GB separated multiple files in case the data exceeds 2 GB.
The DS series manages these separated data files by adding 4 digit numbers starting from 0000
after the file ID to control the data sequence.
If the file IDs are used from 0001 to 9999, the DS creates the file name of FILE#_OVF_0001 to
record. In such case, change and set the file name.
At recording, some control data areas are created, such as a circular recording area, a pretrigger
area, and a post data area. Depending on the recording mode (NORMAL/ENDLESS) and the
pretrigger state, data to be subtracted by the keyword information on the header file involves.
Example File Names
When entering the file name as “TEST” at the browser:
TEST_0001_0000.DAT
TEST_0001_0001.DAT
TEST_0001.HDR
Restart recording after stop
TEST_0002_0000.DAT (0 Byte data or Pretrigger amount)
TEST_0002_0001.DAT (2GB)
TEST_0002_0002.DAT (less 2 GB)
TEST_0002.HDR
XXXX_****_0000.DAT is the pre-data file, and is the pretrigger data at the pretigger mode.
At the normal recording mode, the data size of the file is 0 Byte.
**** indicates the ID number.
The maximum size which can be specified is limited as follows:
| User specify area(78 bytes)
｜
Reserved area 6 bytes
｜
Even though the total size of file name is 84 bytes, The maximum size which can be specified is
78 bytes.
For details on the data file format, please contact us.
・ ・ ・
User specify area(78 bytes)
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