Data Handling Interfaces

SPLC and Direct Interfaces

Instruments may be interfaced directly to the EXPRESS Pallet or may be interfaced to a Standard Payload Computer (SPLC).

The following data interfaces will be available:

• MIL-STD-1553B Data Bus (SPLC, for interfacing with ISS and for payload connectivity);
• RS 232/422 Serial Data (SPLC; with option of RS485 bus payload connectivity in addition);
• Ethernet (SPLC - for interfacing with ISS);
• Analog Multiplexed Interfaces (number tbd - at minimum 8 channel input, 12 bit resolution and 100 Hz sample rate per SPLC );
• Discrete Digital Interfaces (at minimum 12 inputs and 12 outputs per SPLC);
• High Rate Data Link (HRDL - direct connection to EPA). There will be one connection per EP and it is not multiplexed; shared usage between EPAs must be timelined. The HRDL standard is tbd and the rate is tbd Mbps.

Figure 8.1.: shows the SPLC interface concept (preliminary). (tbd)

Data Services During Transport/Installation

Environmental history data are available from the NSTS Shuttle Orbiter whilst the EP is in the cargo bay. At other times the payload has to provide the means if these data are required as there are no data services from the EP during transportation and installation.