4Links tutorials on SpaceWire Test in November 2011

4Links ran a very successful tutorial on SpaceWire Test on the day before the International SpaceWire Conference 2011. The tutorial was followed by an informal reception, to which all conference and exhibition delegates were welcomed. The tutorial was also presented several times in Japan, in the week following the ISC.

The aim of the tutorial was to show how 4Links' SpaceWire test equipment can be exploited at various stages of a space mission:

  • At the Feasibility Study stage, experimental designs are exercised and their performance is evaluated. Interfaces between development computers and SpaceWire components will be required, as well as SpaceWire simulators (e.g. routers and RMAP emulators).
  • At the Project Definition stage, specific designs are implemented, and these prototypes are examined in great detail. Precisely measuring router latencies and response times of instruments might be important to you. The ability to inject fault conditions into your SpaceWire devices will also aid testing.
  • At the Build stage, equipment must be critically tested against its specification and against those of the devices that it will be connected to. Capturing all of the traffic in a SpaceWire network will provide an archive record of the unit-level tests.
  • At the Integration stage, networks of SpaceWire-connected systems must be repeatedly checked for interoperability, and issues rapidly identified and resolved. Analyser tools will help to identify the causes of problems, and SpaceWire recorders again will provide a record of the testing.
  • In the Post-Launch stage, many suppliers and prime contractors retain their test sets, to simulate and analyse unexpected behaviours of the satellite in flight. Our rack-mounted test equipment is robust and easy to secure.

Since most 4Links SpaceWire test units are built around a common hardware platform, it is usually possible to re-configure them through the insertion of extra firmware modules, and therefore to extend their utilisation across all of these phases of the mission lifecycle, which makes them particularly cost-effective.

The breakdown of the tutorial was:

  • Introduction to 4Links and its test equipment architecture.
  • Using the test equipment, together with software supplied by 4Links. We showed how you can answer several versions of the question "Does your design work?".
  • Writing your own test software, using the 4Links C API. We demonstrated how application-specific tests can be written using the 4Links C API, again with some simple examples.
  • Integration support, SpaceWire monitoring, recording, and analysis. We showed how you can answer the questions "Do the devices work together in a system?", "How can I record the SpaceWire traffic from lots of SpaceWire links?" and "How can I analyze the recording?". We did this by analysing a pre-recorded session using a range of new MSR visualisation tools.

There were opportunities during the tutorial and subsequent conference to talk with 4Links staff and many delegates asked them for advice about SpaceWire designs and testing requirements.

Here are two presentations of data recorded by our Multi-link SpaceWire Recorder:

4Links Error Waveforms: Low-level diagnostics with SpaceWire waveform capture

Low-level diagnostics with SpaceWire waveform capture


4Links Multi-link SpaceWire Recorder (MSR): High-level analysis of the traffic on an entire SpaceWire network

High-level analysis of the traffic on an entire SpaceWire network

The presentation material from these tutorials is available for our customers to study.