D.5 RS485
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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
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
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