Re: Few Jornada 690 questions

["Valeriy E. Ushakov" <uwe%ptc.spbu.ru@localhost>]

On Wed, Aug 16, 2006 at 18:32:31 +0200, Adam Wysocki via ArcaBit wrote:

> > That's a wrong approach.  I've just committed a fix as hd64461video.c
> > rev 1.36.
> 

> It works - quite strange, because I tried unblanking with wsblank

Well, in that state the driver didn't turn the screen on, but it
thought it was *not* blanked, so an unblanking request from wsblank
would be "optimized away".  Blanking it first to force internal state
update was a workaround.


> By the way, what's the status of the IrDA and the sound card drivers? And 
> one more thing - is there a method to load my custom font?

I think there should be some mails from me in the archive.  To summarize:

* IrDA.

scif(4) has two problems: it's not bus_space'ified, so it doesn't
support two instances of itself, and there's a bug in the driver that
causes it to lose incoming chars.  The first problem is easy to fix,
it's a pretty machnical change.  I had those mods in my tree, but
didn't want to commit them b/c of the second problem.  The second
problem can be observed if you try to run ppp over the serial, or try
to make a dial-out connection, e.g. to cu to another unix box.
Incoming chars are lost.  I made a few light-hearted attempts to fix
it, thinking that it could be a simple bug, but to no avail so far.
So with the mods that address the first problem and allow you to
attach both scif ports you can talk to IrDA devices, but the second
problem prevent it progress even through the IrDA handshake (yes, I
tried ;).

* Sounds

There's no sound *card* in sh3 jornadas.  There's an on-chip 8-bit DAC
and one of its channels is hooked to the speaker.  You need to feed
the DAC directly from the CPU.  This means that you need to have 8K
interrupts per second to play even crappy lo-fi 8KHz 8bit audio.
There is on-chip DMAC that can do timed transfers using internal
counter-timer, but attempts to use it wedge the machine ~immediately.
WinCE does not use DMAC to feed DAC.

I gave up on the DMAC approach, and I'm too lazy to do the brute force
approach, especially as I'm not interested in playing audio on jornada
:)


SY, Uwe
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