Rockwell Automation Allen-Bradley DriveLogix 5730, Руководство пользователя

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2-2 Placing and Configuring the Drive
protected and must be present. If the associated links are not present, or are
deleted, the communication connection between the controller and drive
will be broken.
The user-defined tags are made up of a fixed number of REAL (floating
point) and DINT (double integer) data types. No links are required within
the drive to support these tags. Therefore, links may be created and deleted
as required with no affect on the communication connection between the
controller and the drive. The user-defined tags may be used to address
application specific data needs not covered by the pre-defined tags.
Mapping for Inputs and Outputs
For each of the 21 inputs and 21 outputs, there a dedicated parameter within
the drive for a total of 42 parameters. Selecting a communication format
defines the data types for each input and output. It also determines the data
type for the dedicated parameter in the drive. The selection also configures
parameters 601 [From DL DataType] and 625 [To DL DataType], which
indicate the data types for each dedicated parameter within the drive.
Determining When the
Controller Updates the Drive The DriveLogix controller follows a producer/consumer model for the drive
connection, similar to the interface to an I/O module. The drive acts as both
an input module, producing data for the controller; and an output module,
consuming data from the controller. Although the producer/consumer
model multi casts data, all data in the drive connection is exclusive to the
DriveLogix controller.
The controller updates the input and output data in the drive connection
asynchronously to the logic scan, consistent with the way it handles other I/
O data. All input data from the drive is read in a single block and all output
data is written to the drive in a single block.
You must configure the Requested Packet Interval (RPI) rate for the drive.
This setting affects how fast the controller reads and writes the data in the
drive interface.
The Drive consumes data from the DriveLogix controller every 2
milliseconds, and produces data to the controller every 2 milliseconds. The
drive updates the inputs and outputs to the controller asynchronous to both
the program scan and I/O scan of the controller.
TIP: If you want data to remain constant throughout one scan, make a copy
of the data at the beginning of the scan and use the copy throughout the
scan.