we will start from the OS selection.....
OS selection should be based on
1)The functional needs of the application.
2)Availability of development tools and technical support.
3)Third party application and developer support.
4)Real time capabilities.
5)Processor architecture and peripheral support.
6)Memory foot print.
8)Conformance to standards
What is real time operating system ?
Real time operating system can be defined as an OS which guarantees a certain capability with in a specified time span.Real time operating systems are commonly found in Robotics,complex multimedia and animations , communications and has various military and government uses.
Some examples of real-time operating systems are Chimera, Lynx, MTOS, QNX, RTMX, RTX, and VxWorks.