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Leon mode in eCos


Hi, I am working on eCos on Leon and I have a few questions about
user/supervisor modes: how are they used inside that OS?
I usually thought that in any OS threads where executed in user mode (S=0 in
PSR register), while all kernel function like scheduling where in supervisor
mode (S=1). Or, at least, that is what I have been taught.
Anyway debugging with cygwin/ddd on the "twothreads" example (two threads
are runned with the scheduler) I always find S=1. both in the kernel (I put
a breakpoint just before context-switch) and in the threads (breakpoints
during execution).
Can I safely assume that the processor is always in supervisor mode?
Thanks,

Michele


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