Download RPC-UserManual

Rosetta
RPC-UserManual
Reference
Issue
Date
Page
: RO-RPC-UM
: Draft
Rev.
: 0.987
: February 20,2002
: 166
Figure 3.1-1: RPC Post Launch Support Organisation
3.1.2 Experiments
3.1.2.1
PIU
All electrical, telemetry and telecommand interfaces between the RPC
group of instruments and the spacecraft are handled by the PIU. This
unit distributes secondary power within the group of instruments, it
provides the first level of command decoding and it controls the
packaging of data for transmission to the spacecraft.
When PIU is powered the nominal mode shall be to have MAG
powered on (one MAG ADC is needed for the PIU HK) as well, but
not producing any Science. The PIU HK will be automatically produced
at power on. Once spacecraft time update has been received PIU will
send an “alive” event and the first packet of housekeeping. MAG
should then be powered on and only after the ADC’s in MAG have
started to send voltage and thermistor values will all of PIU
Housekeeping be valid.
In order for any other experiment in the package be powered PIU and
MAG must be powered (ref. section 3.1.2.6). Commands to any other