Re: Serial VS Diagnostic interface

[Nick Garnett <nickg@ecoscentric.com>]

"damien millescamps" <damien.millescamps@gmail.com> writes:

> On Wed, Jan 14, 2009 at 3:19 PM, Nick Garnett <nickg@ecoscentric.com> wrote:
> > The most common problem with serial devices is not enabling
> > CYGPKG_IO_SERIAL_DEVICES. Obviously you also have to include the
> > CYGPKG_IO_SERIAL package too.
> >
> > Note that AT91 serial devices cannot be shared between diagnostics and
> > serial drivers. So if you want to continue using diagnostics on a
> > particular UART, you need to disable it for the drivers.
> >
> 
> I imagine you mean CYGPKG_IO_SERIAL_<platform> instead of
> CYGPKG_IO_SERIAL_DEVICES which doesn't exist ?

No, I really do mean CYGPKG_IO_SERIAL_DEVICES, which is an option in
the CYGPKG_IO_SERIAL package. It causes the serial devices to be
enabled. If you cannot see it, then that probably means that
CYGPKG_IO_SERIAL is not included or enabled.

> 
> When you say it is not possible to use the Diagnostic interface and
> the serial drivers, is it just because of the ISR declaration ? If
> this is the case, I already know how to handle it, or are you talking
> about another issue ?

It has more to do with the DMA engines. The PDC is used to overcome
the UART's lack of FIFOs. Once the drivers are loaded they point the
DMA engines at their own buffers, not those previously used by the
diagnostic channel. As a result the diagnostic channel code will no
longer work.


-- 
Nick Garnett                                      eCos Kernel Architect
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