RS-485
Sign in to savethumb|Texas Instruments VN08 (SN75HVD08) - Wide Supply Range RS-485 Transceiver RS-485, also known as TIA-485(-A) or EIA-485, is a standard, originally introduced in 1983, defining the electrical characteristics of drivers and receivers for use in serial communications systems. Electrical signaling is balanced, and multipoint systems are supported. The standard is jointly published by the Telecommunications Industry Association and Electronic Industries Alliance (TIA/EIA). Digital communications networks implementing the standard can be used effectively over long distances and in electrically
Key facts
- Fieldbus protocol.name
- TIA-485-A(Revision of EIA-485)
- Fieldbus protocol.standard
- ANSI/TIA/EIA-485-A-1998 Approved: March 3, 1998 Reaffirmed: December 7, 2012
- Fieldbus protocol.physical_media
- Balanced interconnecting cable
- Fieldbus protocol.network_topology
- Point-to-point, multi-dropped, multi-point
- Fieldbus protocol.maximum_devices
- At least 32 unit loads
- Fieldbus protocol.maximum_distance
- Not specified
- Fieldbus protocol.mode_of_operation
- Different receiver levels: binary 1 (OFF)(Voa–Vob binary 0 (ON)(Voa–Vob > +200 mV)
- Fieldbus protocol.available_signals
- A, B, C
- Fieldbus protocol.connector_types
- Not specified
via Wikipedia infobox
Article
13 sectionsContents
- Overview
- Standard
- Full duplex operation
- Converters and repeaters
- Network topology
- Protocols
- Applications
- Signals
- Waveform example
- See also
- Notes
- References
- External links
thumb|Texas Instruments VN08 (SN75HVD08) - Wide Supply Range RS-485 Transceiver RS-485, also known as TIA-485(-A) or EIA-485, is a standard, originally introduced in 1983, defining the electrical characteristics of drivers and receivers for use in serial communications systems. Electrical signaling is balanced, and multipoint systems are supported. The standard is jointly published by the Telecommunications Industry Association and Electronic Industries Alliance (TIA/EIA). Digital communications networks implementing the standard can be used effectively over long distances and in electrically noisy environments. Multiple receivers may be connected to such a network in a linear, multidrop bus. These characteristics make RS-485 useful in industrial control systems and similar applications.
== Overview == RS-485 supports inexpensive local networks and multidrop communications links, using the same differential signaling over twisted pair as RS-422. It is generally accepted that RS-485 can be used with data rates up to 10 Mbit/s or, at lower speeds, distances up to . As a rule of thumb, the speed in bit/s multiplied by the length in meters should not exceed 108. Thus a cable should not signal faster than .