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Using Protocol Macros Section 5-4
5-4-3 Ladder Program Example
The following diagram shows an example in which sequence number 000
(Present Value Read) of a Temperature Controller (E5@K Read Protocol) is
executed using the protocol for an OMRON Temperature Controller connected
to port 2 (RS-422A/485) of a Serial Communications Board.
Connections
Send Word Allocation for Sequence No. 000 (Present Value Read)
Receive Word Allocation for Sequence No. 000 (Present Value Read)
Serial Communications
Board
Port 2
Specifies the Temperature Controller Unit No.,
sends the PRESENT VALUE READ command
send data, and receives the present value set
in the response in the specified word.
Send data
Temperature
Controller E5#K
Unit No. 01
Receive data
Temperature
Controller E5#K
Unit No. 00
32 Units max.
Temperature
Controller E5#K
Unit No. 31
First word of
send data
Number of send data words Contents (data format) Data
(Undefined) Unit No. Number of send data words
(4-digit BCD)
0002 (fixed)
WordS
S + 1 S
S + 1
Unit No.
(2-digit BCD)
00 to 31
Receive data
storage words
Number of receive data words Contents (data format) Data
Present value Number of receive data words
(4-digit BCD)
Present value
(4-digit BCD)
0002
WordR
R + 1 R
R + 1
Scaling
Lower limit to upper limit