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Re: Fw: diag serial port and debug serial port conflict?


"Ling Su" <lingsu@palmmicro.com> writes:

> I met the same problem as descriped in following message, and I tried what
> Nick siad, actually I doubled the ZDEL, the result is the same. Any
> suggestion? Thanks!
> 

I do not now recall what the final solution to this problem was, but I
know it was solved. If Charles is listening, maybe he can remember
what the solution was.




> -Ling
> 
> 
> > "Charles F." <charles@202.96.178.16> writes:
> >
> > > I am sure they are initialized to the same speed. Yesterday I tried to
> use
> > > non-optimization setting (delete the -O2 switch in general build
> settings)
> > > to compile ecos and it works! I guess there is something wrong with the
> > > optimized serial port intialization code. I have experience porting
> WinCE to
> > > 4373 board and once I met this kind of problem too. Am I right?
> >
> >
> > This raises one possibility:
> >
> > The HAL_DUART_WRITE_CR() macro contains a delay loop that is used to
> > keep the Z8530 happy. It looks like with -O2 this loop maybe being
> > eliminated or optimized so it is too short. However, exactly the same
> > code appears in the initialization for the stubs, and GCC shouldn't
> > eliminate such loops. So it is not at all clear what the difference
> > here is.
> >
> > I have just compiled this code with -O2 and it seems to keep the delay
> > loop intact. Maybe your board has a faster CPU? The code is currently
> > set up for a 133MHz part. Try changing the value of ZDEL in
> > plf_z8530.h to something greater (and compiling with -O2) and see if
> > that makes a difference.
> >
> > --
> > Nick Garnett, eCos Kernel Architect
> > Red Hat, Cambridge, UK
> >
> >
> 
> 
> 


-- 
Nick Garnett, eCos Kernel Architect
Red Hat, Cambridge, UK


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