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Date: Wed, 16 Jul 2014 10:50:17 +0200
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Subject: Re: [Qemu-devel] hw/arm: add Lego NXT board
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To: Alexander Graf <graf@campus.tu-berlin.de>, Alexander Graf <alexander.graf@ilr.tu-berlin.de>, Peter Maydell <peter.maydell@linaro.org>
Cc: QEMU Developers <qemu-devel@nongnu.org>

Il 16/07/2014 10:40, Alexander Graf ha scritto:
>>>
>
>> I think that there are two other ways to do it.
>
> And what about the chardev way? Your silence in this regard is
> misterious ;-)

The main problem with chardevs is that they are completely asynchronous. 
  So they may not be a good match for your use case.

(In fact, this is a problem for the i2c-over-chardev and especially 
spi-over-chardev ideas I shot out yesterday.  For i2c-over-chardev one 
could add support to clock stretching in QEMU, but SPI is entirely 
synchronous).

Note that -qmp and -qtest both use chardevs internally to connect the 
external program with QEMU.

Paolo

>>
>> 1) [...]
>> 2) [...]
>
> Thanks a lot for your suggestions. I will play a bit and come back when
> I have some code to show.