Rockwell Automation 1734-APB Point I/O Profibus Adapter Module - Manual (Page 47)

Publication 1734-UM005B-EN-P - June 2001
Communication and I/O Table Mapping 4-9
Operating States
The general system behavior is determined by the operating status of
the master. The 3 main states are:
•
Stop - No data transmission occurs between the master and the
slaves.
•
Operate - The master is in the data transfer phase. In cyclic data
communication , inputs of the slaves are read, and output
information is written to the slaves.
•
Clear - The master reads the information of the slaves and sets
the outputs to an idle state. (Refer to “Configure Idle Action
Value for Your Output Modules,” page 3-11.)
Data_Exchange
After correct set_parameter and check_configuration services, the
master automatically starts exchanging data with the adapter by means
of the data_exchange service.
Slave_Diag
The adapter may notify the master of its current state by means of the
slave_diag service. The information received from this service request
can be divided into 3 parts:
•
Standard diagnostic information according to the PROFIBUS
standard DIN 19245-3
•
Module related diagnostics indicates which I/O module has
diagnostic events pending.
•
Channel related diagnostics, give more detailed information of
the actual cause of the event (wire-break, overcurrent, etc.).