AutomationDirect C0-USER-M Manual page 272

Interlocking
If you are going to use more than one Receive and/or Send instruction with the same
server(slave), you need to be sure only one of the instructions is enabled at any point during
the operation. The technique to execute more than one Receive and/or Send instructions in
order is called 'Interlocking'. When the Interlocking sample program below is executed, one
Receive instruction and one Send instruction is executed one-by-one for each server.
Example Program: Interlocking with Two Servers
Port 1
NOTE: Port 1 can establish the connection with up to 4 servers at the same time.
CLICK PLC Hardware User Manual, 6th Edition, Rev. F – C0-USER-M
Ethernet Network
Server
(IP Address = 10.11.0.3)
1. Execute the Receive instruction.
2. Execute the Send instruction.
Continue these steps.
Chapter 4: PLC Communications
Server
(IP Address = 10.11.0.4)
1. Execute the Receive instruction.
2. Execute the Send instruction.
Continue these steps.
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