Yokogawa JUXTA VJ Series Limit Alarms - Manual (Page 17)

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IM 77J01J11-01E
3.1.2 Configuration of Response
Responses from the VJ Series with respect to a command sent from the higher-level
device consist of the elements shown below, which differ depending on the condition of
communication; normal or failure.
1) Normal Communication
When communication completes normally, the VJ Series returns a character string "OK"
and data corresponding to a command.
Number of Bytes Variable length 1 2 2 2 2 1 1
Element STX Address
number
(ADDRESS)
CPU
number
01
OK Parameter data Checksum ETX CR
030105E.EPS
2) In the Event of Failure
If communication does not complete normally, the VJ Series returns a character string "ER"
and error code (EC1 and EC2). (See subsection 3.1.3, “Response Error Code”.)
• No response is made in case of an error in address number specification or CPU
number specification.
• If a VJ Series cannot receive EXT in a command, response may not be made.
* As a countermeasure, provide a timeout process in the communication functions of the higher-level device or in
communication programs.
Number of Bytes 1 2 2 2 2 2 3 2 1 1
Element STX ER EC1 EC2 Command Checksum ETX CR Address
number
(ADDRESS)
CPU
number
01
030106E.EPS
3rd Edition : Oct. 15, 2007-00