VEGA Modbus-TCP, ASCII protocol - Manual (Page 7)

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1 Function as Modbus-TCP server
Modbus-TCP, ASCII protocol • VEGAMET 391/624/625, VEGASCAN 693, PLICSRADIO C62
30768-EN-130701
Register address in
Modicon
Temporary memory of VEGASCAN (2 words =
4 byte)
31011 PC/DCS output 3: Status
31013 PC/DCS output 4: Measured value
31015 PC/DCS output 4: Status
31017 PC/DCS output 5: Measured value
31019 PC/DCS output 5: Status
31021 PC/DCS output 6: Measured value
31023 PC/DCS output 6: Status
… …
31113 PC/DCS output 29: Measured value
31115 PC/DCS output 29: Status
31117 PC/DCS output 30: Measured value
31119 PC/DCS output 30: Status
As an alternative, register address 41001 is also available as start
address (function code 03).
The actual measured values are transmitted as signed data compris-
ing four octets. In addition to the measured value, the status of the
measured value is supplied in a second register word.
Example of the data of a PC/DCS output
Float Bit 15…0 Float Bit 31…16
Register addr. 31001 Register addr. 31002
High-Byte/Low-Byte High-Byte/Low-Byte
Note:
On the switching inputs of PLICSRADIO C62 (measurement loops
4 … 6) the values 0 (switch open) and 100 (switch closed) are trans-
mitted as measured values; the units are discarded.
984 Floating point: Intel single precision real. First register contains
bits 15 … 0 of 32 bit number (bits 15 … 0 of significand). Second
register contains bits 31 … 16 of 32 bit number (exponent and bits
23 … 16 of significand).
The status describes the condition of the associated measured value.
The content of the measured value is only valid if the corresponding
status has the value zero. If there is a status value unequal zero, the
status value and the corresponding value in the measured value field
must be taken into account in a detailed failure diagnosis. The follow-
ing chart explains the possible faults.
Status Measured
value
Meaning
0 XXXX Valid measured value
Format of the PC/DCS
value
Floating point of OPEN
MODBUS/TCP SPECIFI-
CATION