Can I execute any c made prog without any os platform?

Question

I googled about it and somewhere I read ....

Yes, you can. That is happening in the case of embedded systems

I think NO, it\'s not poss

Answer 1

You definitely don't need an OS to run your C code on any system. What you will need is two pieces of initialization code - one to initialize the hardware needed (processor, clock, memory) and another to set up your stack and C runtime (i.e. intialization of data and BSS sections). This, of course, means that you cannot take advantage of the multithreading, messaging and synchronization services that an OS would provide. I'll try and break it down into some steps to give you an idea:

1. Write a "reset_routine" that run when the board starts. This will initialize the clock and any external memory needed. (This routine will have to execute from a memory that is either internal or one that can be initialized and programmed externally).
2. The reset_routine, after the hardware initializations, transfers control to a "sw_runtime_init" routine that will set up the stack and the globals definied by you application. (Do a jump from reset_routine to sw_runtime_init instead of a call to avoid stack usage).
3. Compile and link this to you application, whilst ensuring that the "reset_routine" is linked to the location where the reset vector points to.
4. Load this onto your target and pray.