Connecting The Data Cables To The Pc - Conrad Electronic 197720 Notice D'emploi

d) Connecting the data cable to the PC
The relay board can be operated individually, but it is also possible to operate several relay
boards in series (cascading).
All boards are controlled via the first connected board.
The first relay board can either be operated via the RS232 port (directly via the clamps TXa,
RXa and GND) or via the USB port (USB operation requires the RS232 USB converter, Conrad
order no. 197257).
The operating mode has to be set via the jumpers JP2 and JP3.
• Connection via RS232 port
For RS232 operation, the jumpers JP2 and JP3 must be plugged on position 1-2.
Computer connection is established via a 9-pole null modem cable (e.g. Conrad order no.
982040).
The control cables can also be connected directly to RXa, Txa and GND:
RXa = data from the control computer to the relay board
TXa = return connection to the control computer
GND = ground
• Connection via USB port
For USB operation, the jumpers JP2 and JP3 must be plugged on position 2-3.
The RS232 USB converter required for operation (Conrad order no. 197257, not part of the
delivery) is plugged into the port "USB adapter" on the relay board.
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