Re: tlug: bt848

[Marcus Metzler <mocm@example.com>]

J. David Beutel writes:
 > On Mon, 6 Jul 1998, A.Tomita wrote:
 > It works in Japanese Win95, but the standard size seems to be 320x240.
 > The drivers and manual are in Japanese, so it's difficult for me.
 > I can't find any rating, but I think that most of the similar cards
 > could do 320x240 at 30fps.  On the other hand, NTSC is 700x525
 > at 30fps?  (262 lines interlaced at 60fps and 4:3 aspect ratio?
 > Or, does the vertical and horizontal blanks cut it down to 640x480?)
That`s right. NTSC cuts down to 640x480.
 > 
 > Soooo, hoping it's just a software limitation, I turn to Linux,
 > which is all I really want to use anyway.  But, I haven't quite
 > gotten it working yet.  The xtvscreen program displays grey lines
 > across the whole width of my monitor, in the vertical area where
 > the TV screen is, when I start capture (overlay).  It clears up
 > when I stop capture.
Hmm, looks like the screen width is not recognized correctly. This
happens for some cards, although it shouldn`t if you have the XF86dga
extension. Try the -rw option in xtvscreen to find the right screen
width. Sometimes for 800x600 the width turns out to be 960 (don`t ask
me why). The gray color comes from the PAL default setting. There is a 
problem with the video4linux specs which only allow to set a TV norm
for a channel (i.e. a tuner channel) and not for the input. I don`t
know if they have fixed that yet. If not, you need to go into the
tuner setting and switch to NTSC and then go back to another input.


 > Does anyone have any hints or ideas about where the problems are?
 > Decoding the video?  Transferring to the display board?  No DMA?  I
 > noticed that BTTV uses PCI definitions for 2 ATI display boards, but
 > mine (PCI_DEVICE_ID_ATI_215CT222) is not one of them.  Is BTTV using the
 > XFree86 direct draw stuff instead?  Or, is that up to the TV
 > application?  /proc/pci reports an IRQ 255 for my display board--that's
 > bogus, right?  What area should I troubleshoot?
I asked my brother and he told me that people seem to have lots of
problems with the ATI boards. He doesn`t know if this is because of
the xfree drivers (as is the case for S3 boards) or if the ATI
hardware in general causes some difficulties. It is pretty hard for us 
to debug this stuff, because we don`t have the boards to test it with.
Maybe you can try the Accelerated X drivers and see if those work
better. That would narrow down the problem. You can get a demo version 
at www.xinside.com.

Marcus

----------------------------------------------------------------------------
Dr. Marcus Metzler
Department of Physics    | $B")(B $B#2#7#4!<#8#5#1#0(B
Toho University          | $B@example.com)A%66;T;0;3#2!<#2!<#1(B
Miyama 2-2-1, Funabashi, | $BElK.Bg3X(B  $BM}3XIt(B  $BJ*M}(B
Chiba 274-8510           | 
Japan			 |
e-mail : mocm@example.com
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