User manual

Computer Gateway User Manual 3-4 5/96
3.2.1
3.2.1 ACP Interface Routines
The application programmer is provided with a number of interface routines that allow him
to give and get LCN data and to perform necessary housekeeping work. The specific
interfaces provided are
•
Get/Store LCN Data
Get Data (multipoint using DDT)
Get Single Value (external ID)
Get Single Value (internal ID)
Store Data (multipoint using DDT)
Store Single Value (external ID)
Store Single Value (internal ID)
Get History (multipoint using DDT)
Get Message
Send Message
• Scheduling and Miscellaneous functions
Get ACP Status
Program Delay
Program Termination
ACP Trap Handler
Check Bad Value
Create Bad Value
Convert External to Internal ID
3.2.1.1 Get Data
This routine fetches point-data values from the CG or elsewhere on the TDC 3000
X
LCN.
The specification of which data is to be fetched and where it is to be stored in the calling-
program's data arrays is contained in the Data Definition Table referenced by the call.
3.2.1.2 Get Single Value (External ID)
This routine fetches data for a single-point parameter (or parameter array) from the CG or
elsewhere on the LCN. The point name, parameter name, and array size if applicable, for
the data to be fetched, as well as the location where it is to be stored in the host processor,
are all contained in the call.
3.2.1.3 Get Single Value (Internal ID)
This routine fetches data for a single point from the CG or elsewhere on the LCN. Use of
the internal point and parameter (or parameter array) address, obtained by previous use of
the Convert Address function, reduces the overhead required for repetitive single-point
requests. The internal identifier of the data to be fetched, as well as where it is to be stored
in the host processor, are both contained in the call.