Rockwell Automation 20-750-PBUS Profibus DPV1 Option Module User Manual
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Rockwell Automation Publication 750COM-UM004B-EN-P - September 2012
Chapter 5 Using the I/O
• The data passed through the Datalink mechanism is determined by the
settings of
Host Parameters 01...16 - [DL From Net 01-16] and Host
Parameters 17...32 - [DL To Net 01-16]
.
• When an I/O connection that includes Datalinks is active, those Datalinks
being used are locked and cannot be changed until that I/O connection
becomes idle or inactive.
• When you use a Datalink to change a value, the value is not written to the
Nonvolatile storage (NVS) memory. The value is stored in volatile
memory and lost when the drive loses power. Thus, use Datalinks when
you need to change a value of a parameter frequently.
Datalinks for PowerFlex 750-Series drive peripherals (the embedded EtherNet/
IP adapter on only PowerFlex 755 drives and option modules such as an encoder
or a communication module) are locked when the peripheral has an I/O
connection with a controller. When a controller has an I/O connection to the
drive, the drive does not allow a reset to defaults, configuration download, or
anything else that could change the makeup of the I/O connection in a running
system. The I/O connection with the controller must first be disabled to allow
changes to the respective Datalinks.
Depending on the controller being used, the I/O connection can be disabled by
doing the following:
• Putting the controller in Program mode
• Disconnecting the drive from the network
• Placing the master in idle mode
DeviceLogix Datalinks are also locked while the DeviceLogix program is
running. The DeviceLogix program must first be disabled to allow changes to the
Datalinks. Set DeviceLogix parameter 53 - [DLX Operation] to ‘DisableLogic’
to disable the logic (the parameter value will then change to ‘LogicDisabld’).
IMPORTANT
A reset is always required after configuring Datalinks so that the
changes take effect.
TIP
A COP (Copy) instruction or a UDDT is needed—for REAL parameters,
speed Reference, and speed Feedback only—to copy the DINT data into
a REAL word for input data conversion. For output data conversion, a COP
(Copy) instruction or UDDT is needed—for REAL parameters, speed
Reference, and speed Feedback only—to copy the REAL data into a DINT
word. To determine whether a parameter is a 32-bit integer (DINT) or a
REAL data type, see the Data Type column in the chapter containing
parameters in the PowerFlex 750-Series AC Drives Programming Manual,
publication