Embedded Systems/Common Protocols

This is a list of common protocols used in embedded systems. Eventually, this list will become hyperlinks to sources of information on each.

• I²C
• RS-485 is an extremely common hardware arrangement used by many embedded protocols:
  • CAN on top of RS485
  • DeviceNet on top of CAN. Wikipedia: DeviceNet
  • NMEA 2000 on top of DeviceNet. Wikipedia: NMEA 2000
  • DMX on top of RS485. Wikipedia: DMX512
  • see Serial Programming/RS-485, Robotics/Computer Control/The Interface/Networks#RS485, Embedded Control Systems Design/Field busses, Embedded Systems/Serial and Parallel IO#RS-485
• MIDI. official MIDI interface schematics (1); beautiful MIDI IN schematic (2).
• BlueTooth
• InfraRed
• ZigBee
• SPI
• RS-232
• USB
• IP Over Serial Connections
• MINES (Microcontroller Interpreter for Networked Embedded Systems) was designed for very small embedded systems (see Gallery of MINES Devices).
• the Tiny Embedded Network
• IEEE Standard for Sensor Transducer Interface
• the three byte Mini SSC protocol (and another Mini SSC protocol example)
• JTAG
• NTSC / PAL television video output: w:TV Typewriter, Generating TV signal by PSoC, Generating TV signal with the PICs, PIC Breakout, ... Parallax Propeller has a video generator ...
• The low-latency Myrinet protocol is used in over 100 of the TOP500 supercomputers, as of June 2005.
• The low-latency InfiniBand protocol is used in over 100 of the TOP500 supercomputers, as of November 2010.
• The various Audio over Ethernet (AoE) protocols are generally designed to be relatively low latency.
• The LIN-Bus (w:Local Interconnect Network), a low-cost vehicle communication network

Further reading

If you are designing a new protocol because none of these meet your needs (which are what, exactly?), you may want to consider the w:Network protocol design principles, some Serial Programming/Forming Data Packets tips, ponder Communication Systems and Data Coding Theory, select one of the Serial Programming/Error Correction Methods, and post rough drafts to the PICA standards wiki for expert review.

Typically an embedded system has one "main" CPU and a bunch of peripheral devices. Is there a way for the main CPU to automatically find out how many peripheral devices are currently connected, and the unique ID of each device? Yes, several ways -- some of them are listed on a page at the Electronics and Robotics site.

• "Consistent Overhead Byte Stuffing" by Stuart Cheshire and Mary Baker, 1999.