Frick QUANTUM LX - Page 41

QUANTUM
™
LX EVAPORATOR CONTROL PANEL
COMMUNICATIONS SETUP
090.610-CS (MAY 2016)
Page 41
Since this is the only address we are interested in
writing to, send the following message:
: 01 06 1B EE 03 E8 05 CRLF
Where:
Message Start:
Quantum™ ID #:
Write Function:
H. O. address (hex):
L. O. address (hex):
H. O. # of Data Value:
L. O. # of Data Value:
Error Correction Code:
Carriage Return - Line Feed:
Look at this message on a more basic level, to
understand how the address that we are writing to
is arrived at. We want to send the value of 1000
(100.0) to the Regulation Mode 1 Setpoint, Frick®
Address 7150 (decimal).
The rst part of the message will be a Colon (:).
This represents a heads up alert that data is com-
ing down the line.
: 01 06 1B EE 03 E8 05 CRLF
Where:
Message Start:
Quantum™ ID #:
Write Function:
H. O. address (hex):
L. O. address (hex):
H. O. # of Data Value:
L. O. # of Data Value:
Error Correction Code:
Carriage Return - Line Feed:
Any time that a message is sent, all of the Quan-
tum™ panels that are on the MODBUS® network
will become active, communications wise, once
the Colon appears. Next, all panels will look at the
rst byte following the Colon (:). If this byte equals
the Panel ID # of the particular Quantum™ being
queried, it will immediately nish reading the re-
mainder of the message. If the byte does not equal
its ID #, the message will be ignored.
: 01 06 1B EE 03 E8 05 CRLF
Where:
Message Start:
Quantum™ ID #:
Write Function:
H. O. address (hex):
L. O. address (hex):
H. O. # of Data Value:
L. O. # of Data Value:
Error Correction Code:
Carriage Return - Line Feed:
}
In this particular example, we are strictly looking
to write a data value, so we will be performing a
write function (06):
: 01 06 1B EE 03 E8 05 CRLF
Where:
Message Start:
Quantum™ ID #:
Write Function:
H. O. address (hex):
L. O. address (hex):
H. O. # of Data Value:
L. O. # of Data Value:
Error Correction Code:
Carriage Return - Line Feed:
}
7150 decimal equals 1BEE hex. Looking at our ex-
ample we see that we need a H.O. (High Order)
address and a L.O. (Low Order) address. Since all
data sent and received is in ASCII Hex Byte format,
we need to look at EE Hex as the Low Order por-
tion of the address. The High Order portion is 1B.
Now our decimal 7150 is formatted as 1BEE Hex.
: 01 06 1B EE 03 E8 05 CRLF
Where:
Message Start:
Quantum™ ID #:
Write Function:
H. O. address (hex):
L. O. address (hex):
H. O. # of Data Value:
L. O. # of Data Value:
Error Correction Code:
Carriage Return - Line Feed:
}
The value that we wish to send is 100.0 (1000).
The Data Value part of the data packet is looking
for a High and a Low Order value. The number
1000 (dec) must be converted to hexadecimal.
This conversion results in a value of 03E8 (hex).
Separating 03E8 into two bytes results in the Low
Order Value of E8 (hex) and the High Order Value
of 03 (hex):
: 01 06 1B EE 03 E8 05 CRLF
Where:
Message Start:
Quantum™ ID #:
Write Function:
H. O. address (hex):
L. O. address (hex):
H. O. # of Data Value:
L. O. # of Data Value:
Error Correction Code:
Carriage Return - Line Feed:
}