Onboard Software Static Architecture

Already in the introduction to chapter 7 it was explained that more S/C onboard units than just the central OBC are in fact computers. And obviously they contain and need onboard software for operation. Besides the computers cited in chapter 7 quite a significant number of microcontrollers are hidden in intelligent sensor and actuator units which including their own embedded software. Typical components providing functions achieved in software are

obviously the S/C platform central OBCs,

instrument / payload control computers and payload data processors (image compression units etc.),

the aforementioned Memory Management and Formatting Units,

Power Control and Distribution Units,

and complex AOCS sensors and actuators such as

the previously mentioned star trackers,

GPS / Galileo / GLONASS receivers,

other position sensors such as DORIS receivers,

as well as fiber-optic gyros and

as well as fiber-optic gyros and

intelligently controlled reaction wheels.