Johnson Controls FRICK QUANTUM HD - Page 50

QUANTUM™ HD COMPRESSOR CONTROL PANEL
COMMUNICATIONS SETUP
090.040-CS (JAN 14)
Page 50
: 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 exam-
ple 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 portion of the ad-
dress. 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):
In order to ensure that the Quantum™ in ques-
tion receives the data request accurately, we
must append an Error Check byte to the end of
the message. This is accomplished by adding
each of the byte pairs (hex) that we have gener-
ated thus far:
01 + 06 + 1B + EE + 03 + E8 = 1FB hex
Normally, we would subtract 1FB (hex) from 100
(hex), as in the previous read example. However,
in this case we see that 1FB hex is greater than
100 hex. Since the math in this particular ex-
ample would yield a negative number (FFFF FFFF
FFFF FF05), we need to modify the value of 1FB
in order to provide a positive result. This is ac-
complished quite simply by dropping the most
left hand digit (1FB becomes FB), and then sub-
tracting FB hex from 100 hex:
100 (hex) - FB (hex) = 05 (hex)
After the entire data packet has been created,
simply press the [Enter] key, a Line Feed will au-
tomatically be sent also.
: 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:
}
: 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:
}
: 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:
}