PC RS485 Interface

Posted on Nov 25, 2012

This interface circuit provides electrically isolated RS485 communication inteface to the PC serial port the isolation circuit protect the PC from direct connection to hazardous voltages.

Click here to download the full size of the above Circuit.

Figure 1 shows the circuit diagram of RS485 interface. Connector K1 is linked to the serial port of the PC, power to the PC side of the circuit is derived from the signal lines DTR and RTS. Positive supply is derived from RTS and negative supply from the

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