2 basic message structure 9, Function block number 9, Function number 9 – West Control Solutions KS 800 ISO1745 Interface Manual User Manual
Page 9: Safety procedure 9, Basic message structure
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Bem. E Addition selection criteria
In order to form a purposeful sub-set from the variety of data, additional selection criteria are defined:
q
Function block number
A function block is addressed by a function block number. It is within ‘0’ and ‘250’ and is appended to
the code field by means of a comma.‘,
Function block number ranges:
w
0general data for the overall instrument
w
1 - 99fixed function blocks
w
100 - 250variable function blocks
q
Function number
A function as a partial address of a function block is addressed with a function number. It is within ‘0’
and ‘99’ and is appended to the function block number by means of a comma.
‘,
Function number ranges:
w
0 - 99Functions
w
0Function General, Default, unless a no. is specified
Bem. F Safety procedure
Correct transmission of a message is supported by two safety procedures:
w
check of each message byte by formation of parity (1 bit per 7 data bits)
w
Check by Block Check Count : safety section, which connects all characters of a message between STX
(excl.) and ETX (incl.) bytewisely by a logic XOR function; length 1 byte, follows always after ETX.
3.2
Basic message structure
Message structure with data transmission:
Computer sends
to KS 800:
EOT
STX
ETX BCC
KS 800 replies:
ACK
or
NAK in case of error
Message structure with data enquiry:
Computer requests:
EOT
ENQ
KS 800 replies:
STX
ETX
BCC
or
NAK in case of error
Message structure
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