Rockwell Automation Allen-Bradley DriveLogix 5730, User Manual

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5-6 Communicating with Devices on a Serial Link
Example 1: Workstation
Directly Connected to a
DriveLogix Controller In the following example, a workstation directly connects to a
DriveLogi5730 controller over a serial link. This is useful for downloading
a controller project directly to the controller.
Use RSLogix 5000 programming software to configure the controller’s
serial port for the DF1 point-to-point (full-duplex) protocol. This type of
protocol supports simultaneous transmission between two devices in both
directions. The DF1 point-to-point protocol controls message flow, detects
and signals errors, and retries if errors are detected.
Configuring a DF1 Point-to-Point Station
This field: Description:
Station address The station address for the serial port on the DF1 point-to-point network. Enter a valid DF1 address
(0-254). Address 255 is reserved for broadcast messages. The default is 0.
NAK receive limit Specifies the number of NAKs the controller can receive in response to a message transmission.
Enter a value 0-127. The default is 3.
ENQ transmit limit Specifies the number of inquiries (ENQs) you want the controller to send after an ACK timeout.
Enter a value 0-127. The default is 3.
ACK timeout Specifies the amount of time you want the controller to wait for an acknowledgment to its message
transmission.
Enter a value 0-32767. Limits are defined in 20ms intervals. The default is 50 (1000ms).
Embedded response Specifies how to enable embedded responses.
Select Autodetect (enabled only after receiving one embedded response) or Enabled. The default is
Autodetect.
Error detection Select BCC or CRC error detection.
Configure both stations to use the same type of error checking.
BCC: the controller sends and accepts messages that end with a BCC byte for error checking. BCC
is quicker and easier to implement in a computer driver. This is the default.
CRC: the controller sends and accepts messages with a 2-byte CRC for error checking. CRC is a
more complete method.
Enable duplicate
detection Select whether or not the controller should detect duplicate messages. The default is duplicate
detection enabled.