3 cyclic communication, Cyclic communication -5, Cyclic communication – KEYENCE DL-EP1 User Manual
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Communi
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- EtherNet/IP Compatible Network Unit DL-EP1 User’s Manual (IL) -
3-3
Cyclic communication
This section describes the cyclic communication functions and how to use them.
What is cyclic communication?
Cyclic communication is a function that exchanges data with the EtherNet/IP device
in a cyclic manner (at a set cycle).
In cyclic communication, data can be exchanged when one device successfully
opens a logical communication line called a "connection" with the other device.
The side which opens the connection is called the scanner, and the side to be
opened is called the adaptor. (The DL-EP1 is an adaptor.)
Cyclic communication is started in the following procedures:
(1) The scanner requests the adaptor to open the connection.
(2) The adaptor side checks compatibility.
(3) If no error occurs as a result the compatibility check, the adaptor opens the
connection.
(* If an error is found during the compatibility check, the adaptor does not open
the connection.)
"Checking the Device Compatibility" (Page 3-21)
Data is exchanged between the EtherNet/IP scanner, DL-EP1 and each sensor
amplifier as follows:
To carry out EtherNet/IP communication with a scanner which does not
support cyclic communication (Allen-Bradley SLC5/05 Series, etc.), use
"Message Communication" (Page 3-22).
(1) Request connection open
(3) Open connection
(2) Check
compatibility
Output data
Data reflected in the
scanner
Input data
The data output from the
scanner is stored by the
DL-EP1.
EtherNet/IP scanner
DL-EP1
Sensor amplifier
IN area
OUT area
Cyclic
communication
Data between
sensors is
refreshed
Cyclic
communication
Data between
sensors is
refreshed
Reference