Emerson Smart Wireless Gateway, Справочное руководство

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Reference Manual
00809-0200-4420, Rev GA
Section 5: Host Integration
April 2013
Host Integration
Figure 5-6. Modbus Register Map Page
To add a new data point to the Modbus register map:
1. Click New entry.
2. Complete all of the table entries for the new data point (note that the entry columns
may vary based on the Modbus communications settings).
3. Repeat for each new data point.
4. Click Submit.
5. When changes have been accepted, click Return to form.
Address: This is the Modbus RTU address used by the Gateway for this data point. It is possible to
group data points assigning them the same address (i.e. all data points from the same process
unit can have the same address). This column only appears if Multiple Modbus Addresses is
selected on the Modbus Communications page.
Register: This is the Modbus register number used for this data value. Modbus registers hold two
bytes (16 bits) of information; therefore 32 bit floats and integers require two Modbus registers.
Each data point needs a unique Modbus register number, unless they are assigned different
addresses. Register numbers 0-19999 are reserved for Boolean (bit, coil, binary, etc…) values.
Register numbers 20000+ are reserved for floating point or integer values.
Point Name: This is a two part name for the data point. The first part is the HART Tag of the
wireless field device which is producing the data. The second part is the parameter of the
wireless field device.
Point Name is entered as <HART Tag.PARAMETER> . Point Name can be entered using the list of
values (…) or manually entered. The following table gives a list of standard device parameters
which may be considered for Modbus register mapping.