A scheduler is a nice example for using a computed call.

Its very useful on statemachines, where many tasks are time controlled.
The advantage, you need only one timer for all tasks and can still run other things until the time expired, no CPU time was wasted.

Following an example code for the AVR:

http://www.mikrocontroller.net/attachmen...hedule.zip

With only small changes it runs also on the 8051 (I developed it originally for the 8051).

Its very fast and need not a huge amount of memory.

For tasks, which should be executed periodically, the task can add itself to the table again. To stop such periodically tasks, simple remove it from the table.

For most of my applications a table of up to 10 tasks was sufficient. Its also no problem to place the table inside the XDATA space or use 16 or 32 bit time values.

For the user it looks like many tasks are executed in parallel.


Peter