Hack a Day. Final Projects ECE 4760. RS-485 (EIA-485) serial interface pinout and wiring. EIA-485 (formerly RS-485 or RS485) is an OSI Model physical layer electrical specification of a two-wire, half-duplex, multipoint serial connection. The standard specifies a differential form of signalling. The difference between the wires? Voltages is what conveys the data. One polarity of voltage indicates a logic 1 level, the reverse polarity indicates logic 0. The difference of potential must be at least 0.2 volts for valid operation, but any applied voltages between +12 V and -7 volts will allow correct operation of the receiver. EIA-485 is better described as un-balanced interface, as the balanced normallly implies that the voltages on the differential wires are balanced with respect to ground or earth potential (eg +5V and -5V), but EIA-485 is usually +5V and 0V .
EIA-485 only specifies electrical characteristics of the driver and the receiver. Handbook of hardware pinouts, cables schemes and connectors layouts. Engineer’s Bookshelf. Embedded Books Reading Room. Embedded Systems, Conference, development,real-time, programming, emulators, multitasking, debugging, software,optimization, engineer, RTOS, chips, tools, microcontrollers,DSP,operating systems,kernel,microprocessors,object-oriented,single board,ada,C++,v.
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