[ECOS] Re: DSR question

[Nick Garnett]

t.michals@attbi.com writes:

> yes this is what is happening, the DSR unmasks the 
> interrupt causing the the ISR to retrigger before the 
> DSR is completed.  So this can cause a deadlock issue?  
> I thought this should just retrigger the DSR again? 

While in theory eCos should be able to handle this, it is not really
designed to deal with it. The exact behaviour is undefined. 

Depending on things like exactly where in the ISR and DSR the
interrupt mask and unmask come, it is possible for a continuously
interrupting source to stack up frames and maybe overflow the
interrupt stack. This is the most likely cause of your problems.


-- 
Nick Garnett - eCos Kernel Architect
http://www.eCosCentric.com/

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