User manual

Computer Gateway User Manual 4-44 5/96
4.6
4.6 POINT-DATA TRANSFERS USING DATA TABLES
The following group of data-transfer messages require the use of previously built and
converted Internal Data Tables (Internal DDT). See paragraph 4.5 for descriptions of the
messages used in Internal DDT preparation, and for table format and content.
4.6.1 Get Data Request (Internal DDT in CG)
This message from the host processor is used when a copy of the Internal DDT is kept by
the CG (see paragraph 4.5.3).
Eight-Character Tagname Form
Header information: Word 1—Transaction Code = 3
Word 2—Number of Words = 10
Word 5—CG Identifier = 2
Message format: Words 1..4—ACIDP name or blank (8 ASCII characters)
Word 5—data access priority (integer) 1=control
2=noncontrol
Words 6..10—Internal DDT name (9 ASCII characters followed
by a blank character)
Use information: The referenced Internal DDT must be previously created
(messages 6 and 9) and stored in the CG database (messages 10
and 12) with no errors reported.
Sixteen-Character Tagname Form
Header information: Word 1—Transaction Code = 103
Word 2—Number of Words = 19
Word 5—CG Identifier = 2
Message format: Words 1..8—ACIDP name or blank (16 ASCII characters)
Words 9..13—reserved for future use
Word 14—data access priority (integer) 1=control
2=noncontrol
Words 15..19—Internal DDT name (9 ASCII characters followed
by a blank character)
Use information: The referenced Internal DDT must be previously created
(messages 106 and 9) and stored in the CG database (messages 10
and 12) with no errors reported.