Spectris Particle Measuring Systems LiQuilaz II E, Руководство по эксплуатации

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Appendix B RS-485 Communication Protocol
LiQuilaz II E and S Operations Manual Page B-11
Formatting Data
The data is in straight binary format with an STX at the start of the packet and an ETX
at the end. Since the STX and the ETX may be valid values in the actual data, the
following data formatting algorithm must be used to prevent confusion between data
in the packet and delimiting characters:
FORMAT ALGORITHM:
packet = STX B1 B2 ...BK ...BN ETX
-----------------------------------------------------------------------------------------
if Bk equals STX, ETX or FF(hex)
transmit FF(HEX)
transmit Bk exored with 80(hex)
else
transmit Bk
Since the node does not respond to any commands other than those sent to its
address, the host computer will initiate a Fast protocol transmission by sending a
single 8-bit address character on the network. The lower 7 bits of this character will
have a value between 0 and 99 that corresponds to the node’s main network address.
The upper (most significant) bit of the address character will be a 1, indicating that a
Fast protocol response is being requested. After recognizing its address, the node
responds with the following report with each line describing a single character.
Note that this is the unformatted packet, before it is sent to the format algorithm.
<STX>
ADDRESS
SI.4
SI.3
SI.2
SI.1
LASER/FLOW STATUS
SAMPLE_STATUS
DC_LIGHT.2
DC_LIGHT.1
NUMBER_CHANNELS
CHANNEL1.4
CHANNEL1.3
CHANNEL1.2
CHANNEL1.1
CHANNEL2.4
CHANNEL2.3
CHANNEL2.2
CHANNEL2.1
CHANNEL3.4
CHANNEL3.3
CHANNEL3.2
CHANNEL3.1
:
.
CHANNELn.4
CHANNELn.3
CHANNELn.2
CHANNELn.1
CHECK_SUM.2
CHECK_SUM.1
<<ETX>>