VEGA Modbus-TCP, ASCII protocol User Manual
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2 ASCII protocol
Modbus-TCP, ASCII protocol • VEGAMET 391/624/625, VEGASCAN 693, PLICSRADIO C62
30768-EN-130701
Number of bytes
Character
Identifier
1
?
Begin
1 … 3
001 … 030 or 1 … 30
Separator
1
-
End
1 … 3
001 … 030 or 1 … 30
End identification
1
CR
•
Identifier: "?" (1 character)
•
Start: Start no. of the requested PC/DCS output (1 … 3 charac-
ters)
•
Separator: "-" (1 sign)
•
End: End no. of the requested PC/DCS output (1 … 3 characters)
•
End identification: Carriage Return CR (1 sign)
Total length of the telegram: 5 … 9 characters
(End-Start+1)-times repetition of the following telegram
Number of bytes
Character
T1
1
=
DCS no.
3
001 … 030
T2
1
#
Value
7
-000673
T3
1
#
Unit
0 … n
xxx
End identification
1
CR
•
T1: "=" (1 character)
•
DCS no.: No. of the PC/DCS output as 3-digit decimal number
•
T2: "#" (1 character)
•
Value: Numerical value of the PC/DCS output or with interferred
measured value the text "FAULT"
Formatting of the value:
Character
Meaning
1
"- ": Minus with negative numbers
" ": Space with positive numbers
2 … 7
6-digit number after the decimal point
•
T3: "#" (1 character)
•
Unit: Unit as text (0 … n unit)
•
End identification: Carriage Return CR (1 sign)
Total length of the telegram: (End-Start+1)*(14 characters+Unit
character)
Enquiry:
?001-003
Answer:
Enquiry of the control
system
Reply from the signal
conditioning instrument
Example: