GE Embedded Field Agent, User Manual

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GFK-2993F 79
For public disclosure
6.2.3.2 Configure a Modbus TCP Data Source
The steps to configure the Modbus Machine Adapter are:
1. Open the file com.ge.dspmicro.machineadapter.modbus-0.xml for editing.
2. Edit the data contained within the dataNodeConfigs and dataSubscriptionConfigs elements to specify the following:
a. Each channel element corresponds to a Modbus Slave Server from which this program will read values.
•
The protocol should be set to TCP_IP.
•
The tcpIpAddress should be set to the IP Address of the Modbus Slave Server:
•
For MFA, replace 127.0.0.1 with the IP address of the Modbus Slave Server.
•
For EFA on CPE400, the tcpIpAddress element defaults to using localControllerHost for
connecting to the Modbus Slave Server through an internal interface. localControllerHost is
a hostname assigned to the internal virtual NIC to communicate with the controller.
•
For EFA on UCSC, replace localControllerHost with the IP Address of the Modbus Slave
Server.
•
The tcpIpPort will most likely be set to 502 , which is the reserved port for Modbus
communications.
•
regBaseAddress is an optional parameter whose value is either 0 (the default) or 1 . This controls
whether the Machine Adapter uses zero or one-based addressing for the registers. If set to 1 , the
Machine Adapter will subtract one from each register address configured for this Slave Server.
•
bitBaseAddress is an optional parameter whose value is either 0 (the default) or 1 . This controls the
whether the Machine Adapter uses zero or one-based addressing for bit offsets within a register.
•
defaultModbusByteOrder is an optional parameter whose value is either true (the default) or false .
This controls whether the byte order is interpreted as the default Modbus byte ordering (big endian)
or the Intel byte ordering (little endian).
•
first16BitLow is an optional parameter whose value is either true (the default) or false . This
controls whether the Machine Adapter interprets the first 16 bits of a 32-bit data type to be the low
or high word of the 32-bit value.
•
first32BitLow is an optional parameter whose value is either true (the default) or false . This
controls whether the Machine Adapter interprets the first 32 bits of a 64-bit data type to be the low
or high double word of the 64-bit value.
•
mostSigBit is an optional parameter whose value is either true or false (the default). This controls
whether the Machine Adapter should use Modicon bit ordering which reverses the bit order.
b. The unit corresponds to a Modbus Slave Address, also known as the Slave ID.
c. Modbus registers.
•
The name element contains the tag name as it will appear in the Predix Cloud. The name should be
unique amongst all of the variables from any Field Agent that will be going to this same Time
Series Database.
•
The dataType element possible values are: BOOLEAN, BYTE, SHORT (2 byte integer),
INTEGER (4 byte integer), LONG (8 byte integer), FLOAT (4 byte real), DOUBLE (8 byte real)
and STRING.
•
The address is the register or coil number to be read.
•
The registerType element possible values are: HOLDING, INPUT, COIL and DISCRETE
d. Each dataSubscriptionConfig represents a group of Modbus registers to be read and published to the Predix
Cloud at a given interval.
•
The name attribute represents the name of the subscription, which is used in section Configure
Sending Data to the Predix Cloud .
•
The documentation for the remaining attributes can be found in the link below.
•
Each nodeName element corresponds to a name defined for a register, in the dataNodeConfigs
section of the xml file.
3. Save and close com.ge.dspmicro.machineadapter.modbus-0.xml .
Note
All time stamps made by the Modbus Machine Adapter will be in UTC (Coordinated Universal Time).
Note
Additional information on configuring the Modbus Machine Adapter, including options for each configuration item,
can be found by searching for “Modbus Machine Adapter” in https://docs.predix.io .