Omron TJ2-MC64 - PROGRAMMING Programming Manual page 250

Communication protocols
Comparison of the actual configuration and the registered table
When unit dipswitch 1 is set to ON, an I/O configuration table is registered in
the GRT1-ML2, and the GRT1-ML2 is turned on, the GRT1-ML2
automatically compares the actual I/O configuration and the registered table.
If a registered SmartSlice I/O Unit cannot participate in he I/O
communication, or if the GRT1-ML2 detects an unregistered SmartSlice I/O
Unit, a verification error occurs. In this case, the concerned SmartSlice I/O
Units do not participate in the I/O communication. The I/O communication
starts with the other SmartSlice I/O Units.
The tables above give an example of a mismatch between the registered
table and the actual configuration. The I/O data sizes of the third unit do not
match. Therefore, a verification error occurs and the third unit does not
participate in the communication.
The TS LED flashes red when a verification error occurs.
PROGRAMMING MANUAL
fig. 19
From left I/O Bits
#1 Input 4
#2 Input 4
#3 Output 4 Mismatch
#4 Output 2
Registered table
From left I/O Bits
#1 Input 4
#2 Input 4
#3 Output 2
#4 Output 2
Actual configuration
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