User`s manual

GFK-2334A Chapter 5 PROFIBUS Master Status and Diagnostics 5-5
5
Communication Requests
The Communication Request function (COMMREQ) allows the program to communicate
with a GE Fanuc intelligent module, such as a PROFIBUS Master. For details on the
operation of the COMMREQ function block, refer to appendix A.
The figure below illustrates the flow of information between the PLC CPU and the
PROFIBUS master.
Communications Request Operation for PROFIBUS Master
The PROFIBUS Master CPU supports the following COMMREQ tasks and responses.
Task Name Description
Page
No.
1 Get Device Status
Retrieves detailed status information for the specified
node.
5-6
2 Get Master Status Retrieves detailed status information for the Master. 5-9
4
Get Device
Diagnostics
Retrieves diagnostics for a specified Slave.
5-14
5 Read Module Header Retrieves module header information. 5-16
6 Clear Counters Clears counters in ReadModuleHeader 5-18
7 DPV1 Read Request Performs a DPV1 read request from a slave device. 5-19
8 DPV1 Write Request Performs a DPV1 write request to a slave device. 5-21
9 DPV1 Alarm Request Acknowledges a DPV1 alarm request. 5-24
The following table lists the memory types that can be used for the Status Block and
Reply Data areas.
COMMREQ Status Word Memory Type Codes
Memory Type
Abbreviation
Memory Type
Decimal
code to enter
%I Discrete input table (BYTE mode) 16
%Q Discrete output table (BYTE mode) 18
%R Register memory 8
%AI Analog input table 10
%AQ Analog output table 12
%T Discrete temporary memory (BYTE) 20
%M Discrete internal memory (BYTE) 22