So Proper Video Out Is Hard To Implement On Pandora, Huh?

[_VWV_]

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http://www.hy-research.com/beagle_mid.html


Yeah, there might be bandwidth issues like the ones that N8x0 has, but still.. We were told it was hard to implement.

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[Chip]

What on earth are you talking about?

 

[gruso]

Apparently we should be able to give Pandora a HDMI out just because someone did it with a Beagleboard... :rolleyes:

VWV, it was already known that the Beagleboard could do this. The Beagleboard is not the same as Pandora. We haven't been misled.

[edit] Also, http://www.gp32x.de/board/index.php?showtopic=47429
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http://www.gp32x.de/board/index.php?showtopic=47429

 

[_VWV_]

Wait a second.. We're told it was too hard to add another display driving chip (because OMAP3 cant drive two high-res video out). That's what I'm talking about.
@gruso, can you please give me a link where beagle drives 2 displays at the same time? Thanx!
As far as I know, beagle has 1 high-res video out which is occupied by video cable in panda - that was the reason why we cant have display + HDMI.. I'm I wrong somewhere?

 

[Butterman]

Whoa, that think is lameeeeeeee.

 

[Chip]

The Beagleboard has always had an HDMI port. It has an HDMI framer chip instead of an LCD interface chip. What this guy did was hijack the digital signal on its way to the HDMI chip and sent it to a homemade LCD interface board. You could do the opposite in the Pandora (hijack and convert to HDMI externally), but you'd end up with a similar mess of wires and an extra board that wouldn't fit in the case.

It's the same signal going to both converters - the built-in HDMI and the hacked-in LCD.

 

[EvilDragon]

Yup, the OMAP can't handle two HD out at once. TV Out and internal LCD should be fine

And as Chip already said: The HDMI out that the Beagleboard uses is the signal bus the LCD in the Pandora uses, so LCD and HDMI at the same time is not possible, only LCD and TV Out (that's why we used it).

Those two displays are independent though, so you can output an emulator or video through TV Out and have something different on the LCD.

 

[_VWV_]

Yes, thanks Chip, I see you've got it. For sure I agree with you it would be a complete mess to hijack video out in panda. There is now place in the current case.. I'm just disappointed it was not done during development. In this case we could have had a proper case with no wire mess with nice HDMI. I think everybody agrees it's the only feature "missing" in Panda.
It turned out to be relatively easy (the guy offers help for other people willing to repeat his experience) to make this mod - that's what deepens my disappointment.
Even if it's the same signal going to both converters, we still could have used HDMI (first one could disable the LCD then one could increase resolution and view the picture on a nice 1024x768 screen - just dreaming).
Edit: typo

 

[gruso]

@gruso, can you please give me a link where beagle drives 2 displays at the same time? Thanx!
Here's one.
http://openpandora.wordpress.com/2009/03/1...-persia-agrees/
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http://openpandora.wordpress.com/2009/03/16/nulldc-making-rapid-progress-prince-of-persia-agrees/


Some info on DVI/HDMI: http://elinux.org/BeagleBoard#Interfacing_to_Raw_LCD_Panels
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http://elinux.org/BeagleBoard#Interfacing_to_Raw_LCD_Panels


The BeagleMID in question seems to be using an additional board for the LCD (and it's only running at PSP resolution).

 

[Chip]

I'm just disappointed it was not done during development. In this case we could have had a proper case with no wire mess with nice HDMI. I think everybody agrees it's the only feature "missing" in Panda.
It's not like you can just throw something like that in. This was seriously considered during the early design phases, but it just wasn't feasible. There simply isn't room on the Pandora board for the necessary hardware. Adding HDMI would have required an extensive redesign with at least one (possibly two or three) additional PCB layers. The overall size of the Pandora would have to be made larger, and the price would have gone up considerably.

 

[_VWV_]

@ Gruso : From your first link:
"The BeagleBoard can drive raw LCD panels through its DVI port by interfacing through an external LCD driver board".

And I asked about beagleboard alone! The same LCD driving board could have been added to Panda. I don't see any difference.

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@Chip: But that man didn't add additional layers to beagleboard.. He added additional LCD driving board (as far as I can see, I'm not an expert). I can agree that additional layers are needed to merge a beagle (which is essentially a panda) with LCD driving board. And this would have drastically increased the price. But it seems there could have been a relatively cheap two-boards design. I might be wrong here, it's just a supposition.

 

[WizardStan]

I think everybody agrees it's the only feature "missing" in Panda.
I emphatically disagree. There are a lot of features which I would have included long before giving it HD output. It's a handheld, I intend to use it as such, and adding yet another interface to it could do nothing but decrease its mobility, if even slightly.

 

[Chip]

But that man didn't add additional layers to beagleboard.. He added additional LCD driving board (as far as I can see, I'm not an expert). I can agree that additional layers are needed to merge a beagle (which is essentially a panda) with LCD driving board. And this would have drastically increased the price. But it seems there could have been a relatively cheap two-boards design. I might be wrong here, it's just a supposition.
And where would that second board go, exactly? Whether you add layers and size to a single board or you add a second board, you are still adding bulk, complexity and cost to the unit.

Not every possible feature could be added and still keep the Pandora pocketable and affordable. The line had to be drawn somewhere. The benefit just wasn't worth the detriments.

 

[Squidge]

There a lot of other features that could have been included in Pandora as well, but there was a target price that we didn't want to exceed, therefore the non-essential features, such as adding a DVI encoder chip and then a decoder chip to convert back to the LCD which will be used most of the time was left out of the design. You could split the path from the OMAP to both an external connector (which you attach a DVI encoder board) and the LCD, but then you have problems with impedence matching, reflecting signals due to unterminated connections, etc. Since both components and time cost money, just the LCD was connected.

 

[_VWV_]

Thanx for the replies! So you think that beagle mod costs a fortune.. Ok, got it. I hope the moder will show us the cost, I'm curious about it.
Any way the problem can be solved (to some extent) with a usb-to-vga adapter.

 

[echidna]

My question is: do we really need to have 2 differents signal on the device? is that enough to just route the one we have from one port to another and make sure THAT will be bullet/idiots/bugs proof?

 

[WizardStan]

Thanx for the replies! So you think that beagle mod costs a fortune..
It doesn't need to cost a fortune. It could cost as little as $5 to add the tech for DVI, but you still need to draw the line somewhere. It only costs $5 to add DVI, so add it. Oh, it's only $5 for tilt sensing, so in it goes. It's only another $5 for a low level GPS, and now you know where you are. Another $5 for a simple camera? done! Only $5 gets you a lot of things, one at a time.
But everything adds up, each cheap feature has their cost, plus additional development costs. Some things are left in, some need to be cut out; you cannot include everything. The devs decided that DVI wasn't important enough to be included, and given that they built a handheld portable device, I enthusiastically support that decision. If it had been a free feature, no real additional cost, no added development required (like how we got bluetooth) then yes, I'd be all for it; there'd be no reason not to.
But there are additional costs, especially in designing the circuit as described: costs in terms of time and space, not just money.

 

[Loonie]

I think everybody agrees it's the only feature "missing" in Panda.

Many's the time I sit there on the metro on the way to/from work thinking "*sigh*... if only I could connect this pocket computer to the 58" plasma screen I always carry around with me".

 

[Monk]

I think everybody agrees it's the only feature "missing" in Panda.

Err, no. I htink you've had some great replies (esp. WizardStans) but, no. We have S-Video Out and that should be more than enough for me, as I hope not to carry around a huge HDMI telly everywhere I go. I'd put a camera, better keyboard, even GPS as more important than HDMI myself.

Ta

 

[fischju2000]

So could it be done with a mess of wires (ending in a non-hdmi/dvi plug on the back) and an external board to do signal processing?