ECSS-E-ST-50-12C – SpaceWire – Links, nodes, routers and networks (31 July 2008)

This Standard has been superseded by ECSS-E-ST-50-12C Rev.1 (15 May 2019)


This Standard specifies the physical interconnection media and data communication protocols to enable the reliable sending of data at high‐speed (between 2 Mb/s and 400 Mb/s) from one unit to another. SpaceWire links are full‐duplex, point‐to‐point, serial data communication links.

The scope of this Standard is the physical connectors and cables, electrical properties, and logical protocols that comprise the SpaceWire data link.

SpaceWire provides a means of sending packets of information from a source node to a specified destination node. SpaceWire does not specify the contents of the packets of information.

This Standard covers the following protocol levels:

  • Physical level: Defines connectors, cables, cable assemblies and printed circuit board tracks.
  • Signal level: Defines signal encoding, voltage levels, noise margins, and data signalling rates.
  • Character level: Defines the data and control characters used to manage the flow of data across a link.
  • Exchange level: Defines the protocol for link initialization, flow control, link error detection and link error recovery.
  • Packet level: Defines how data for transmission over a SpaceWire link is split up into packets.
  • Network level: Defines the structure of a SpaceWire network and the way in which packets are transferred from a source node to a destination node across a network. It also defines how link errors and network level errors are handled.

This Standard may be tailored for the specific characteristics and constraints of
a space project in conformance with ECSS‐S‐ST‐00.


Md5 checksum .doc file = A81215FB306CC92F71D89D185E10FB07
Md5 checksum .pdf file = C3B1357D0819D2BA9CBFA6359028C0C2

This standard cancels and replaces ECSS-E-50-12A (24 January 2003).