Byteflight

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Byteflight is an automotive databus created by BMW and partners Motorola, Elmos Semiconductor and Infineon to address the need for a modernized safety-critical, fault tolerant means of electronic communication between automotive components. It is a message-oriented protocol. As a predecessor to FlexRay, byteflight uses a hybrid synchronous/asynchronous TDMA based means of data transfer to circumvent deficiencies associated with pure event-triggered databuses.

Contents

It was first introduced in 2001 on the BMW 7 Series (E65).

Eclipse 500 jet aeroplanes use Byteflight to connect the avionics displays. [1]

Data frame

In Byteflight terminology, a data frame is called a telegraph.

A telegraph starts with a start sequence containing six dominant bits. This start sequence is followed by a one byte message identifier. This is followed by a length field indicating the length in bytes of the transmitted data. The telegraph ends with a 15 bit CRC value encoded in two bytes leaving the LSB unused. [2]

All bytes are framed by a recessive start bit at the beginning and a dominant stop bit at the end.

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References

  1. Eclipse 500 Avionics Architecture diagram in "Eclipse 500 Avionics" (PDF). Smartcockpit.com. December 20, 2007. Archived from the original (PDF) on February 15, 2016. Retrieved 2016-02-10.CS1 maint: discouraged parameter (link)
  2. Cena, G.; Valenzano, A. (2004). "Performance analysis of Byteflight networks". Proceedings. WFCS 2004 - 2004 IEEE International Workshop on Factory Communication Systems, September 22nd - 24th, 2004, Vienna University of Technology, Vienna, Austria. Piscataway, NJ: IEEE. pp. 157–166. doi:10.1109/WFCS.2004.1377701. ISBN   0-7803-8734-1.