ProSoft Technology ILX69-PBM - Manual (Page 115)

ILX69-PBM ♦ CompactLogix or MicroLogix Platform Contents
PROFIBUS Master Communication Module User Manual
ProSoft Technology, Inc. Page 115 of 124
February 4, 2015
9 Annex
In This Chapter
 PROFIBUS Functionality .....................................................................115
 Disposal of Electronic Equipment Waste .............................................117
 References ..........................................................................................117
 Glossary ...............................................................................................118
9.1 PROFIBUS Functionality
9.1.1 DPV0 Services
PROFIBUS DPV0 services refer to the cyclic data exchange mechanism between a class 1
master and a slave. PROFIBUS DP defines two types of masters:
 A class 1 master handles data communication with slaves assigned to it
 A class 2 master is used for commissioning purposes
In a PROFIBUS message, class 1 masters and slaves transmit up to 244 bytes. Valid station
addresses on a PROFIBUS network range from 0 to 126.
Fail Safe Mode
For safety reasons, the ILX69-PBM informs the slaves of its current control status at certain
intervals using a "Global Control" message. If the ILX69-PBM goes to Clear Mode, the Fail
Safe enabled slaves will switch to a Fail Safe state. Slaves capable of the Fail Safe state
can be configured to either to hold the last state of the outputs or set its outputs to "0".
Slaves that do not support the Fail Safe state set their outputs to "0".
Global Control
With the Global Control message, the ILX69-PBM can send unsolicited commands like
Sync/Unsync, Freeze/Unfreeze and Clear Data to a slave or a group of slaves for
synchronization purposes. Group membership is defined during network start-up and in
ProSoft fdt Configuration Manager.
Sync and Freeze
Sync and Freeze are optional commands where slaves do not need to support them. The
slaves must be able to process the Global Control message. With a Freeze command, the
ILX69-PBM prompts a slave or a group of slaves to "freeze" their inputs to the current state.
A Sync command causes the current output data to latch at their current state until the next
Sync message arrives. Unfreeze and Unsync cancel each corresponding state.