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vsh82-de-110318
4.2.2
Communication Protocol
Communication is carried out according to the Thyracont protocol. The
commands are sent as ASCII-code in the following command frame:
Address
Code
Data
cks
CR
Address:
3 Bytes, decimal; address space RS485: 001 – 999
Code:
1 Byte, command parameter, upper case character for read
command, lower case character for write command
Data:
data field, max. 6 Bytes; can be absent depending on code
cks:
1 Byte, checksum, defined as sum over all Bytes of the fields
address, code and data, modulo 64 plus 64.
CR:
Carriage Return (0Dh, 13d)
Data Formats:
BOOLEAN
1 Byte
STRING:
max. 6 Bytes
UNSIGNED INT:
6 Bytes with leading zeros
FLOAT:
6 Bytes, exponential format
4 Bytes mantissa (means mantissa value x 1000)
2 Bytes exponent, offset 20
FLOAT-values are transmitted in hPa (mbar)!
Example: Value "460016" in a float type data field means 4.6x10
-4
mbar.
Interface-Parameter:
9600 baud, 8 data bits, 1 stopbit, no parity
4.2.3
Survey of Commands
The transducer responds to type queries, measurement queries, adjustment
commands, degas commands (chapter 4.3) and commands for setting gas
correction factors (chapter 4.4).
Programming of the two relay switchpoints is also done via RS485 (chapter 4.5).
Further special parameters can be configured, which determine the general
behaviour of the sensors (see chapter 4.6 and 4.7).
Summary of Contents for VSH82
Page 1: ...VSH82 Vakuum Messumformer Vacuum Transducer Betriebsanleitung Operating Instructions...
Page 23: ...23 vsh82 de 110318...
Page 26: ...26 vsh82 de 110318 Konformit tserkl rung...
Page 48: ...48 vsh82 de 110318...
Page 51: ...51 vsh82 de 110318 Declaration of Conformity...
Page 52: ...vsh82 de 110318...
