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D.5 RS485
Up to 64 LCIC-WIM boards may be connected to one PC port.
In the
PC side
, use a converter either from the RS232 port, or from the
USB port (that is, RS232 to RS485 converter, or USB to RS485
converter). In the
board side
, use the serial port (CONN3) – refer to the
table in the beginning of this appendix.
Using the LCIC-WIM-SETTINGS utility, each board is assigned a
unique address between 1 and 64 – refer to section 3.3.2.1.3 (
never give
the same address to more than one board
).
An RS485 board may be either ‘active’ or ‘inactive’. An ‘active’ board
honours all commands, while an ‘inactive’ board honours only the RS485
address handling commands. Upon board reset it ‘wakes up’ inactive. A
board
starts
being active when it receives
its
‘activate board’ command
and
stops
being active when an ‘activate board’ command to any other
board is sent. Hence, only one board (at most) may be active at the same
time.
About the handling of the RS485 address while coding your application
please refer to the RS485 Commands and RS485 Responses sections
below, which expand the summary given in section 4.1/h (‘RS485:
Address selection, setting & reading’).
When a board is configured as an RS485 device, its address
is shown for a while on the LED display upon board reset, for example
“rS.485-18” for the board addressed 18.
