Definitions(continued) Operating system software-Manages the computers resources such as input/output devices, memory, and scheduling of application software Application software- Mission-specific software which does work required by the user or the mission rather than in support of the computer
Definitions (continued) • Operating system software – Manages the computer’s resources, such as input/output devices, memory, and scheduling of application software • Application software – Mission-specific software which does work required by the user or the mission rather than in support of the computer
Computer System Specification 1. Allocate mission and system requirements to computer systems 2. Define the computer system's operational modes and states 3. Functionally partition and allocate the computational requirements to space or ground, payload or spacecraft, individual systems, and to hardware or software
Computer System Specification 1. Allocate mission and system requirements to computer systems 2. Define the computer system’s operational modes and states 3. Functionally partition and allocate the computational requirements to space or ground, payload or spacecraft, individual systems, and to hardware or software
Computer System Specification 4. Evaluate internal and external interfaces 5. Select the baseline architecture 6. Form the baseline system specification
Computer System Specification 4. Evaluate internal and external interfaces 5. Select the baseline architecture 6. Form the baseline system specification
State Transition diagram ibit Prelaunch Standby Intelize or Trevel Fallure Resolve Checkout OK OK Failure On-station Self Teet Hard Eor Fallure Contingent Checkout Resolved
State Transition Diagram
Functional Partitioning Perform processing Perform processing In space d on ground Perform processing Perform processing In hardware In sottware Allocate processing do not allocate between spacecraft processing between bus and payloads spacecraft bus and ds payloads Allocate processing Do not allocate along processing along organizational lines organizational lines
Functional Partitioning P e r fo r m p r o c e s s i n g i n s p a c e P e r fo r m p r o c e s s i n g o n g r o u n d P e r fo r m p r o c e s s i n g i n h a r d w a r e P e r fo r m p r o c e s s i n g i n s o ft w a r e A l l o c a t e p r o c e s s i n g b e t w e e n s p a c e c r a ft b u s a n d p a y l o a d s D o n o t a l l o c a t e p r o c e s s i n g b e t w e e n s p a c e c r a ft b u s a n d p a y l o a d s A l l o c a t e p r o c e s s i n g a l o n g o r g a n i z a t i o n a l l i n e s D o n o t a l l o c a t e p r o c e s s i n g a l o n g o r g a n i z a t i o n a l l i n e s