Hello ngeronikolos,

Rs485 is simply the transmission means to send serial data from one device to many. You use a RS485 transceiver connected to the same pins on the PIC that you would connect a RS232 interface and then you can send and receive your data as you would regular RS232. You will need to create the software that will talk to the individual slaves. Search this forum as there have been articles written about RS485. You can also get Jan Axelson's great book on the SERIAL PORT. It has alot of examples of RS485 communications.

BobK