Communication Protocol; Survey Of Commands - thyracont VSH82 Betriebsanleitung

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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
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
STRING:
UNSIGNED INT:
FLOAT:
FLOAT-values are transmitted in hPa (mbar)!
Example: Value "460016" in a float type data field means 4.6x10
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).
Data
1 Byte
max. 6 Bytes
6 Bytes with leading zeros
6 Bytes, exponential format
4 Bytes mantissa (means mantissa value x 1000)
2 Bytes exponent, offset 20
cks CR
-4
mbar.