Engineering
WirelessHART Fieldgate SWG70
70
E Hauser
10.3
Configuring Modbus
NOTICE!
• The "Modbus" function is only available on WirelessHART Fieldgate models with versions
"SWG70-xx-1-xx-xx" and "SWG70-xx-2-xx-xx". See Chapter 2.3 "Ordering information" on
10.3.1 Modbus Settings
Modbus Settings
determines how the Modbus information is to be transmitted by Fieldgate
SWG70 and where the information is to be found. It also allows the selection of automatic
or manual mapping. The set-up of the Modbus communication parameters (address, baud-
rate etc.) is described in Chapter 8.4.4.
More details on the Modbus Interface itself and the way in which the HART parameters are
mapped to the Modbus registers is to be found in. See Chapter 16 "Modbus Interface" on
1. Click on
Engineering => Modbus Mapping => Modbus Settings
to open the dialog:
Modbus parameters
Parameter
Meaning
Example
Default
Swap Option
Selects frame format swap option for Modbus data
transmission (see also Chapter 16.1.3)
• Big Endian: no swap;
Register 0 Register 1
Source bytes: [0xABCD] [0xEFGH]
Target bytes: [0xABCD] [0xEFGH]
• Little Endian: Register swap;
Register 0 Register 1
Source bytes: [0xABCD] [0xEFGH]
Target bytes: [0xEFGH] [0xABCD]
The Swap Option does not apply to the Input Status registers
Big Endian Big Endian
Addressing Method
Selects whether the mapping is to be done automatically or
manually
• Auto: Mapping is done automatically according to the rules
described in Chapter 16.2
– There is no automatic mapping of Input Status
– The dialogs Input Status and Input Registers are
deactivated
• Manual: Mapping is done manually or semi-automatically in
the Input Status and/or Input Register dialogged
Manual
Auto
Read Modbus
Registers Mode
Determines in which registers the mapping is to be done
• Input Registers only: Values mapped to Input Registers
300001 to 365536
• Input and Holding Values mapped to Input Registers
300001 to 365536 and Holding Registers 400001 to
465536
Inactive
Inactive