User manual

Computer Gateway User Manual 4-94 5/96
4.8.1
Sixteen-Character Tagname Form
Header information: Word 1—Transaction Code = 150
Word 2—Number of Words = 39 plus size of the Internal DDT
table
Word 5—CG Identifier = 2
Message format: Words 1..8—ACIDP name or blank (16 ASCII characters)
Words 9..13—reserved for future use (fill with integer zeros)
Word 14—history type (integer)
0=snapshots at 60-second interval
1=hourly averages
2=shift averages
3=daily averages
4=monthly averages
5=user averages
6=reserved for future use
7=monthly averages at fast interval
8=sampling rate enquiry
9=snapshots at 5-second interval
10=snapshots at 10-second interval
11=snapshots at 20-second interval
Word 15—history mode (integer) 0=absolute
1=relative
Words 16..26—beginning date and time (22 ASCII characters)
Words 27..37—ending date and time (22 ASCII characters)
Word 38—beginning offset (integer)
Word 39—ending offset (integer)
Word 40—start of Internal Data Table
Use information: Common information—The data table follows the Internal DDT
format as defined in paragraph 4.5. The number of
point/parameters is limited to 24. (Because of message size
limitations, the maximum number of point parameters in a request
for one hour of snapshots is 19.) See paragraph 4.8.2 for other
restrictions on the amount of data that can be returned to a history
data request.
The direction of search can be either forward (oldest to newest
data) or backwards (newest to oldest data); however, a forward
search requires at least twice as long to execute. To execute a
backward search using offset values, set the starting offset value
less than or equal to the ending offset value.
There is a limit of 262 samples per call.
Absolute requests—Beginning and ending date and time apply to
only absolute history requests. For relative history requests, these
fields should be blank (spaces).
Date and time format used in absolute history requests is
MM/DD/YY HH:MM with eight trailing blank characters.