it will not be known at compile time what the tasks are. That's what I am working on now. The ability to upload a compiled object file (IHX format, for example) to the 80c552, have it allocate space and task structures for it, run it, then send the results back to the caller. This is what a "real" O/S does. It has to be able to deal with tasks it has no a priori knowledge of. Don't worry though, I will post NONE of it here.