YOKOGAWA UT150L, Руководство пользователя

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IM 05C01E22-10E
4-8
08 Performs a loop back test.
●
Function
This function code is used to check connection for communication.
• For the format of response in the event of failure, see subsection 4.2.4.
• The specification of a D register number (marked with an asterisk below) for a loop back test is
“00” (fixed).
• Any value can be selected for send data.
●
Message (for normal operation)
Element
Number of bytes in
RTU mode
Number of bytes in
ASCII mode
1
Send Data
(Upper Digit)
2
Start of
Message
Mark (:)
None
1
Send Data
(Lower Digit)
1
2
Error
Check
2
2
Address
Number
(ADR)
1
2
None
End of Message
Mark
(CR + LF)
2
Function Code
(08)
1
2
00
(Upper Digit)
1
2 2
1
00
(Lower Digit)
Message (continued)
●
Response (for normal operation)
Element
Number of bytes in
RTU mode
Number of bytes in
ASCII mode
1
Send Data
(Upper Digit)
2
Start of
Message
Mark (:)
None
1
Send Data
(Lower Digit)
1
2
Error
Check
2
2
Address
Number
(ADR)
1
2
None
End of Message
Mark
(CR + LF)
2
Function Code
(08)
1
2
00
(Upper Digit)
1
2 2
1
00
(Lower Digit)
Response (continued)
●
Example: Sending data 1234h to UT150L with address number 05 to check connection for
communication.
The following message sends “1234” (hexadecimal) to address number 05 in the ASCII mode.
[Message] [ : : ]050800001234AD[CR][LF]
Start of message mark
“05”: address number 05, “08”: function code 08, “0000”: fixed, “1234”: send data, and “AD”: error
check
* Numbers in quotation marks are hexadecimal.
When connection for communication is normal, the following response is returned with respect to the
above message.
[Response] [ : : ]050800001234AD[CR][LF]
“1234”: send data