I wish to develop a very small operating system; maybe just the context-switching mechanism would be enough for my needs.

Main reason is curiosity, not an actual need.

I've found the FreeRTOS operating system for my AT91SAM7X device (ARM7TDMI processor within), but although it has only three files for it's kernel, I find it too complicated to learn from and understand. (don't even know where to start)


Any suggestions for a fast-learner-newbie about how to learn to develop a tiny operating system?

I appreciate your time & effort.

Best regards,
Dor.

 

I am not sure there is any rule as to what constitutes an operating system. I n years past, something that let you load a block of tape or dump a portion of core memory to a teletype was pretty good.

Just decide what function/s are useful and write some code to run at boot.

 

look at Micro/OS-II it is a real time kernel that meets requirements for safety-critical systems, which is more of what you are talking about, an operating system usually involves more than just context switching and pre-emptive actions...., amazon has a book available too (http://www.amazon.com/MicroC-OS-II-...ef=sr_1_1?ie=UTF8&qid=1259277732&sr=8-1-fkmr1)

My .02

 

I am not sure there is any rule as to what constitutes an operating system. I n years past, something that let you load a block of tape or dump a portion of core memory to a teletype was pretty good.

I would say every time you program a uC to do a specific task. You have given that system an OS

 

hi,
look at the avrdos from bascom
jp

 

+1 on getting the uCOS/II (Jean Labrosse) book - it will teach you alot and provides a fairly basic, but effective task scheduling kernel. It has been the start of many successful project/developments in cubicle-land.