PIC Based RS485 Multiplexer

Posted on Nov 14, 2012

I decided to implement this using a PIC 16F84 for both an encoder and decoder, and use RS-485 drivers (DS26C31 and DS26C32) to drive the 350m cable. I only needed five I/O pins per PIC, so this could have been implemented using the smaller 8pin 12C508 device, but the 16F84 has the advantage of being reprogrammable, and PCB size or cost wasn`t an issue anyway. The design presented here can be easily modified for any number of bits and any desired interface RS-232, Fibre optic, almost anything.

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kumar Jul 14, 2008

rs485 using in pic

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