2. Configuring an I/O Master
Modbus RTU
Setting
Description
amount of time “gathering” data before sending out the radio link.
l
0 (Disabled) - The radio sends data out through its radio link as soon as
the data is received into the serial port. This is the default setting
l
1 - The radio waits for a number of slots equal to two times the Master
Packet Repeat setting before sending the received data out the radio link.
For example, if the Master Packet Repeat parameter is set to
3
, the radio
waits for 6 slots, gathering data up the whole time. At the end of the 6
slots, the radio sends all received data in one “burst.” This is the
appropriate setting for most Modbus RTU devices.
l
2 or higher - The radio waits for a number of slots calculated using the
following formula:
(Modbus RTU s Master Packet Repeat s 1) x 2
Example
: In a radio where the
Modbus RTU
setting is
2
and the
Master Packet Repeat
setting is
3
, the radio waits for (2 + 3 + 1) x 2,
or 12 slots.
2.4.5 Serial Interface
Serial Interface
Setting
Description
Default Setting:
(0) RS232
Options:
l
(0) RS232 - Also used for TTL.
l
(1) RS422 -
l
Modbus RTU
must be enabled
l
Turn Off Delay
set to at least
4
.
l
(2) RS485 -
l
Modbus RTU
must be enabled
l
Turn Off Delay
set to at least
4
.
l
(3) DOT -
l
DOT causes the CD line to indicate when data is transmitted on the
serial port from the radio.
l
When the radio is not sending data to the serial port, CD is de-asserted.
l
When the radio is sending data to the serial port, CD is asserted.
l
The CD line no longer has any radio link state functionality.
Page 32 of 131
LUM0008AG Rev Sep-2015
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Summary of Contents for FGR2-IO-IOE
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