3 modbus register, General configuration of the host, Holding register – VEGA VEGAPULS SR 68 Modbus and Levelmaster protocol User Manual
Page 72: Input register
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10 Supplement
VEGAPULS SR 68 • Modbus and Levelmaster protocol
41371-EN-130624
Parameter
Configurable Values
Default Value
Parity
None, Odd, Even
None
Stop Bits
1, 2
1
Address range Modbus
1 … 255
246
Start bits and data bits cannot be modified.
General configuration of the host
The data exchange with status and variables between field device and host is carried out via
register. For this, a configuration in the host is required. Floating point numbers with short prevision
(4 bytes) according to IEEE 754 are transmitted with individually selectable order of the data bytes
(byte transmission order). This "Byte transmission order" is determined in the parameter "Format
Code". Hence the RTU knows the registers of the VEGAPULS SR 68 which must be contacted for
the variables and status information.
Format Code
Byte transmission order
0
ABCD
1
CDAB
2
DCBA
3
BADC
10.3 Modbus register
Holding Register
The Holding registers consist of 16 bit. They can be read and written. Before each command, the
address (1 byte), after each command, a CRC (2 byte) is sent.
Register Name Register Num-
ber
Type
Configurable
Values
Default Value
Unit
Address
200
Word
1 … 255
246
-
Baud Rate
201
Word
1200, 2400,
4800, 9600,
19200
9600
-
Parity
202
Word
0 = None, 1 =
Odd, 2 = Even
0
-
Stopbits
203
Word
1 = None, 2 =
Two
1
-
Delay Time
206
Word
10 … 250
50
ms
Byte Oder (Float-
ing point format)
3000
Word
0, 1, 2, 3
0
-
Input register
The input registers consist of 16 bits. They can only be read out. Before each command, the ad-
dress (1 byte) is sent, after each command a CRC (2 bytes) is sent.
PV, SV, TV and QV can be adjusted via the sensor DTM.