QB50 System Requirements Document

5.3 Command & Response Handling5.3.1 OBC Sending a Command PacketThere is no checksum or handshake scheme implemented in order to keep theoperation of the SU as simple as possible.5.3.2 OBC Error Handling of Science UnitThere shall be a nominal time-out set at 60 sec (TBC) in the OBC for responses tocommands. The maximum time-out period shall be 220 sec.On a time-out, the OBC shall ABORT the current script, and TURN OFF the SU. TheOBC shall also generate an ERROR report packet to indicate the error. Theimplementation of the ERROR packet is specific to each CubeSat team.CubeSat:TX CMDtoSUCubeSat:IdleStartTime-OuttimerReachedTime-OutError:GenerateERROR reportpacketError:Turn OFFSUError:ABORTScriptFigure 5-1 OBC SU-Error Handling State Diagram