4Links Multi-link SpaceWire Recorder Version 4, User Manual

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3. Specification
3.1. SpaceWire Links
The SpaceWire Links conform to ECSS-E-ST-50-12C (31st July 2008).
3.1.1. SpaceWire Receive Performance
Receive speeds may be in the range from 1.2 Mb/s to more than 400 Mb/s [the lower-limit is set by the SpaceWire
standard timeout period of 850 ns]. The edge separation on the SpaceWire signal lines must be greater than 1.4 ns.
3.1.2. SpaceWire Connectors
Eight standard 9-way Micro-miniature D-type SpaceWire socket connectors are mounted either on the front
panel (on RG hardware platforms) or on the rear panel (on RG-R platforms).
The connectors are labelled 1 to 8, from left to right, corresponding to software and API ports 1 to 8 respectively.
The pinout of the SpaceWire socket connectors (looking from the outside of the EtherSpaceLink unit) is shown in
figure 3.1:
Figure 3.1: SpaceWire connector pinout
The female “Din” and “Sin” contacts provide inputs to the MSR; the female “Dout” and “Sout” contacts carry
output signals from the MSR.
All eight of these signals are buffered within the MSR using LVDS buffers for each of the differential signal pairs.
Within the MSR, all signal grounds are bonded to the chassis of the unit. Notice that the ground potential
difference between each device-under-test must be held within each receiver’s input common-mode voltage
range.