Johnson Controls Frick QUANTUM LX, Настройка

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QUANTUM™ LX COMPRESSOR CONTROL PANEL
COMMUNICATIONS SETUP
090.020-CS (APRIL 13)
Page 50
In this particular example, we are strictly looking to
request to view a data value, so we will be perform-
ing a read function (03):
: 01 03 07 D3 00 01 21 CRLF
Where:
Message Start:
Quantum™ ID #:
Read Function:
H. O. address (hex):
L. O. address (hex):
H. O. # of Data Registers:
L. O. # of Data Registers:
Error Correction Code:
Carriage Return - Line Feed:
}
2003 decimal equals 07D3 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 D3 Hex as the Low Order portion of the ad-
dress. The High Order portion is 07. Now our decimal
2003 is formatted as 07D3 Hex.
: 01 03 07 D3 00 01 21 CRLF
Where:
Message Start:
Quantum™ ID #:
Read Function:
H. O. address (hex):
L. O. address (hex):
H. O. # of Data Registers:
L. O. # of Data Registers:
Error Correction Code:
Carriage Return - Line Feed:
}
Since we are only looking for this one address, and
no other, we can say that we are only looking for
one Data Address. Our Data Address part of the data
packet is also looking for a High and a Low Order
value. Fortunately, the number one (1) is the same in
decimal as it is in Hex, therefore, the Low Order Ad-
dress is 01 (hex). The High Order Address is 00 (hex),
so our decimal 1 is formatted as 0001 (hex).
: 01 03 07 D3 00 01 21 CRLF
Where:
Message Start:
Quantum™ ID #:
Read Function:
H. O. address (hex):
L. O. address (hex):
H. O. # of Data Registers:
L. O. # of Data Registers:
Error Correction Code:
Carriage Return - Line Feed:
}
In order to ensure that the Quantum™ in question re-
ceives 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 generated thus far:
01 + 03 + 07 + D3 + 00 + 01 = DF hex
Next, subtract DF (hex) from 100 (hex):
100 (hex) - DF (hex) = 21 (hex)
After the entire data packet has been created, simply
press the [Enter] key, a Line Feed will automatically
be sent also.
: 01 03 07 D3 00 01 21 CRLF
Where:
Message Start:
Quantum™ ID #:
Read Function:
H. O. address (hex):
L. O. address (hex):
H. O. # of Data Registers:
L. O. # of Data Registers:
Error Correction Code:
Carriage Return - Line Feed:
}
ASCII Write Example
To demonstrate how an address within the Quan-
tum™ LX may be written to, the following test can
be performed using Windows HyperTerminal ( NOTE :
Hyperterminal cannot be used to test RTU or TCP/IP
communications).
As an example, a MODBUS® command will be cre-
ated and sent to the Quantum™ to set Regulation
Mode 1 Setpoint to 100.0 PSIA. First, be aware that
data sent to and received by the Quantum™ has one
decimal place assumed. This means that to send the
value of 100.0, you actually need to send 1000. Using
the address tables found later in this manual, locate
the address for the Regulation Mode 1 Setpoint. In
this case, it would be Frick® Address 7150 (decimal).
: 01 03 07 D3 00 01 21 CRLF
Where:
Message Start:
Quantum™ ID #:
Read Function:
H. O. address (hex):
L. O. address (hex):
H. O. # of Data Registers:
L. O. # of Data Registers:
Error Correction Code:
Carriage Return - Line Feed:
}