[Kwintv] Re: The old KWinTV hangs with DMA enabled

[Zsolt Rizsanyi]

On Sunday 22 February 2004 00.06, Andras Mantia wrote:
> On Sunday 22 February 2004 00:08, Andras Mantia wrote:
> >  I think it's a kwintv bug, as I cannot reproduce it either with
> > xawtv or qtvision. The problem is: if DMA access for the HDD is
> > enabled, the whole system hangs
>
> Forget the mail as it happens also with QtVision, if I select the XVideo
> port 77. I suppose that in that cases overlay is used and direct
> transfer of the picture from the tuner to the video card through the PCI
> bus. Am I right? Anyway, if you know a fix for my problem, I'd be glad
> for it. Right now, I'm compiling a new kernel...

Hi!

I had a very similar problem, but with different hardware: Leadtek Winfast 
2000 Xp tv card, and AliMagik 1 motherboard. With an earlier motherboard 
(Asus KT133) the problem did not manifest itself.

If I would run QtVision with v4l interface, there would be no problems, 
with XVideo it would crash in at most 60 seconds.
Turning of the DMA on the hard drive did not really help just lessened the 
chance of the freeze (and it could work even for hours).

I have contacted the video4linux list, but they could not help, because it 
is a hardware bug. They said only the manufacturer can help.

So I contacted Ali. They have sources for linux kernel drivers on their 
site, but those are not maintained anymore. It seems their linux crew have 
disappeared.
A developer of the windows driver replied to my query and suggested to try 
out some bios settings, and to set the latency timer of the tv device to 
10. (though I could already find this info in various FAQs on the NET)
That did help, but it would still freeze when there was heavy hard drive 
io.

To get some more usefull information I had to explicitly ask them to list 
the exact changes that happened in the recent releases of the windows 
driver. It turned out I need to set some magic bit on my multimedia card 
(besides the latency set to 10).

So this would be my story, to cheer you up ;)

Good luck
Zsolt