Tamas Rudnai wrote:

> You do not really need a scheduler, you can use the existing techniques
> like:
> 
> - Interrupts
> - Polling technique
> - Mix the two above
> - Combining these with a state machine
> 
> If you think in that way interrupts are like an event driven scheduler,
> while polling is like a cooperative one...

This is usually done in one endless loop, where you call each "task" 
repeatedly in sequence. These tasks then do some work and return, or 
return right away. They may use state machines to keep track of their 
state. 

Typically, if you want to get close to a "real" real-time system, you 
keep the time each task occupies small compared to the required response 
time. This is the cooperative aspect. 

Gerhard
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