ProSoft Technology ProSoft i-View - Manual (Page 34)

Data Source Files ProSoft i-View ♦ Mobile Process Monitoring and Control Application
User Manual Version 2.0.2
Page 34 of 106 ProSoft Technology, Inc.
September 29, 2011
MODBUS GLOBAL
ATTRIBUTES
TYPE DESCRIPTION
rtu_mode number
(boolean) ProSoft i-View will use "Modbus/RTU over TCP" instead
of "Modbus/TCP". This will allow for accessing serial
modbus/RTU devices behind an Ethernet-to-serial
gateway not supporting MBAP. Use the 'slave_id' attibute
on tags to route commands to the right modbus slave
node.
Word_swap number
(boolean) Swaps words for 32-bit data (such as DINT or REAL)
before sending to or upon receiving from a Modbus
device. Nonzero values are 'true.' Default value is ‘false.’
Byte_swap number
(boolean) Swaps bytes for 16-bit or 32-bit data before sending to or
upon receiving from a Modbus device. Nonzero values
are ‘true.’ Default value is ‘false.’
The combined effect swap attributes is as follows:
Assuming a default of 'ABCD' for a byte order where 'A' is the Most Significant Byte (MSB) and 'D'
is the Least Significant Byte (LSB), you can combine Word_swap and Byte_swap with the
following results:
1- word_swap:=false; byte_swap:=false; will give 'ABCD' for 32-bit values and 'AB' for 16-bit
values.
2- word_swap:=false; byte_swap:=true; will give 'BADC' for 32-bit values and 'BA' for 16-bit
values.
3- word_swap:=true; byte_swap:=false; will give 'CDAB' for 32-bit values and 'AB' for 16-bit
values.
4- word_swap:=true; byte_swap:=true; will give 'DCBA'. for 32-bit values and 'BA' for 16-bit
values.
Note: These attributes are only meant for Modbus communications and are ignored for the rest of
the supported protocols.