Hello ! I have a little problem. I have two devices interconected by two wires ( the power lines GND and +5V ) and I have to transmit small ammount of data between them. I must not use rf modules. The cable length is 2 metters. In fact the master device poewres the slave. I have to put a PIC in the slave and send some data to a PIC in the master device using the +5v line. I thought about poewring the slave device with 9 volts ( and inside the slave to pass the voltage through 7805 ). Before 7805, in the slave, to put a transistor, and in the master device, on the power line, another transistor,In this way, I think I can modulate somehow the voltage, and, using a kind of Manchester coding scheme, .... to solve somehow the problem. This is just a theoretical ideea. Does anyone have another ideea ? Or do you think that my ideea might work ? Any schematic would beHIGHLY apreciated ).
Thank you very much for your time.