User manual

Computer Gateway User Manual 4-50 5/96
4.6.4
Use information: The number of point/parameters is limited to a total of 300 or less.
See heading 4.1.5. The Internal DDT used by this request must
be previously created (messages 6 and 9) with no errors reported.
Because of the possibility for errors in point and parameter
definition, caution in use of this message type is advised. One
suggested technique is to read and check the data values before
attempting to change them.
The store status controls what—if any—value is to be stored.
0=Store the data value provided
1=Store the bad value representation instead
2=Do not store any value
Store status value of 1 is valid only for Real or ASCII data. The
bad value representations are NaN for Real values and question
mark strings for ASCII.
The result from a store status of 1 depends on the point type. For
reals and integers, NaN (-0) is stored. For ASCII values and
enumerations, strings of question marks are stored.
The "do not store" (store status = 2) allows for selective storing to
a portion of the points named by the Internal DDT. Return status
for these points is set to 255 (Directed no store).
For further information on standard enumerations, see the
Hiway Gateway Parameter Reference Dictionary.
Process Manager Parameter Reference Dictionary.
Computer Gateway Parameter Reference Dictionary.
Sixteen-Character Tagname Form
Header information: Word 1—Transaction Code = 105
Word 2—Number of Words = 14 plus size of data
Word 5—CG Identifier = 2
Message format: Words 1..8—ACIDP name (16 ASCII characters)
Words 9..13—reserved for future use (fill with integer zeros)
Word 14—data access priority (integer) l=control
2=noncontrol
Word 15—start of Internal DDT table (see paragraph 4.5)
Word 15+Internal DDT table length—start of parameter values (in
same order as in Internal DDT).
Parameter value formats: Real Words 1 and 2—value (real)
Word 3—store status (integer)
Integer Word 1—value (integer)
Word 2—store status (integer)