On Thursday 28 December 2006 11:33, Rudy Zijlstra wrote:
> Luke McKee wrote:
> >Does anyone want to help me reflash my TVeeprom?
> >Is the TVEeeprom used to make assumptions about the card model and
> >region used in mythtv code?
>
> Not really. Its the ivtv driver which reads the EEPROM and based on
> that will report capabilities to any application querying it.
> The Firmware will use the EEPROM to know what initialisation to use
> on the card.
But the tuner model can be overridden by using the ivtv 'tuner' module
option.
>
> >Is it easy to change a tuner? It's only got a few pins, I could just
> >check the datasheets, and use another tuner to work with mythtv.
>
> Unless you are experienced with soldering, its a perfect way of
> making it fully non-functional. This type of soldering needs very
> good temperature control. The soldering iron you need for that, can
> cost about as much as a new PVR350. You would also need to re-flash
> the EEPROM. And to do that you again need some special equipment. And
> detailed knowledge of the card design (both the layout and the
> electrical design).
>
> >I did have it working for a few hours using the SVHS input. It's
> > just now it's gone out to lunch and I'm trying to find out why.
>
> If you remove power for several minutes, it may start working again.
For the record: NTSC and PAL recording should work fine for S-Video and
Composite inputs. Of course, the antenna input is limited to what the
tuner can handle.
>
> >I am working on a LIRC project to make an external tuner using my
> > DVD recorder. I haven't even bothered to test the tuner.. unless
> > anyone knows a PAL tuner is capable of working.
> >
> >Rudy: What your saying is that there are design deficiencies with
> > the PVR hardware to prevent NTSC devices playing PAL signals?
>
> If you want to look at it that way.... Actually no, its simply that
> in cases like this assumptions, and the resulting design choices,
> play a big role. Its not so much a deficiency as a limitation.
>
> Basic assumption 1:
> if somebody lives in NTSC country, the likelyhood he will move to PAL
> country is low (for the reverse the same is true),
> Assumption 2:
> Most people will use the tuner as main input, and the other inputs
> are additional, for "special" usage. Anyway
> Assumption 3:
> When in NTSC, you will not encounter PAL (and the reverse).
>
> Again, this third assumption is something like 99% correct...
>
> HW fact: Building a device that can handle both PAL as well as NTSC
> is possible, but expensive. Even your high-end TV which is always
> multistandard, can only handle either NTSC or PAL on its tuner.
> Essentially you have to include 2 tuners. Take a look at the
> mentioned 3 assumptions (which happen to be based on statistical
> fact), and you start knowing why it is not done.
>
> Business fact: in Mass Production each cent counts, and has a visible
> result on the financial bottom line. Most people do not realise this,
> but Consumer Electronics really is cut-throuth on cost (unless in
> really really high-end).
>
> All in all you end up with a product where although the basic design
> can easily handle both NTSC and PAL, the actual implementation for a
> particular area will almost always be limited to one of them. Also in
> the sections which are generic.
There are several cards available that have a worldwide tuner, either
based on the philips tda9840/tda9875 chips or on the XCeive 3028
(2028?) tuner. The first is supported out-of-the-box, the second is
still work in progress but it expected to be supported in 2.6.22.
Hans
>
> Regards,
>
> Rudy
>
> >Cheers,
> >
> >Luke
> >
> >On 27/12/06, Rudy Zijlstra <[EMAIL PROTECTED]> wrote:
> >>Luke McKee wrote:
> >>>Hello all,
> >>>
> >>>
> >>>
> >>>I have a PVR-350 NTSC version and I'm in a PAL country. I have
> >>>over-rided the standard with PAL=M, and in full debug it seems to
> >>> be putting the card in PAL mode. I also use v4l2-control to do
> >>> this.The MSP44xx seems to support pal audio even though it is not
> >>> listed in the module options.
> >>
> >>I have some strong doubts on whether you can get this to work in a
> >>stable way. Not because of any limitation on the main chipset (cx,
> >>msp,..) but because of the tuner.
> >>
> >>NTSC is a 6MHz bandwidth. PAL is either 7 or 8MHz. This means that
> >> when you use an NTSC tuner in PAL country, you will not capture
> >> all the signal. Especially on an 8MHz PAL signal you will loose
> >> way too much information. On a 7MHz you may get lucky and capture
> >> enough of the signal to get image / sound. I suspect though, that
> >> you will most often loose out on audio. I suspect the tuner will
> >> lock on the video carrier, and the audio carrier will at least
> >> partly be outside the SAW filter of the tuner. On an 8MHz PAL this
> >> will certainly be the case.
> >>
> >>Using SVHS will work around this problem. What i do not know, is
> >> whether the only difference between NTSC / PAL version is the
> >> tuner, or whether the routing on the card is also different. Hans
> >> may know this, having gone through the code in detail on this.
> >>
> >>A different problem you can run into, is that the firmware of the
> >> card may be making some assumptions. Like that when the tuner is
> >> an NTSC, then certain combinations are "unexpected" and thus not
> >> supported in the firmware. This is not so much a concious "not
> >> supported" as well as "not foreseen to be used". The latest can
> >> lead to some very dificult to debug problems.
> >>
> >>Good luck! (i suspect buying a PAL version will safe you a lot of
> >> time and effort).
> >>
> >>
> >>Rudy
>
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