no erik i was not turned off.my processor is 80552.i shall use it in instruments in my section.it needs multitasking.so the effort.
as for xa i understand it is 68000+8051.so some very generous things like a big external ram based stack is available.so the architecture of that os may not be exactly suitable for old8051 arch.this is ofcourse my hunch.i have not verified it yet.
thanks for advice
pranav phatak