Operating a CC Pandora with only TV-Out; 480i Component Video

[TheGrandPubaa]

Edit: I'm terribly sorry, I appear to have posted this in the Pyra forum. My apologies for the inconvenience. Could a moderator move this to the actual Pandora forum?

Hey there. So my original Pandora had it's ribbon cable replaced once and that cable eventually failed as well, so my unit has been collecting dust due to my inability to get the unit mailed out to get it fixed. I've found it really doesn't work all that well as a throw it in my pocket and go portable system in terms of it's durability, so I was curious if it would be feasible to use it exclusively as a home system hooked up to a TV and just not bother fixing the LCD. Is it possible to do a fresh install of the OS set up to output video to a TV by default without being able to see the LCD at all? Likewise, is it possible to operate the Pandora without a battery?

This brings me to my next question. I recently picked up a good condition Sony Wega 20 inch CRT television. It is a SDTV that has component inputs, which is great. The downside is that it doesn't have S-Video. If the above scenario is indeed viable, is there a way to tap component video from the Pandora's TV-Out cable? My Wega only supports up to 480i so i'm not asking for an HD signal, but component is obviously going to produce a superior image compared to composite.

Thanks for reading.

 

[levi]

Yes, this is how I've been running my Pandora for years now after I shorted out the LCD socket on my mobo and had to remove it. When you reflash you unit, TV out will be on by default (although probably in composite mode and hopefully 480i), and from there you can set it to output in s-video (s-video is pretty damn good for a 480i signal - it's a lot better than composite). You can split s-video out into its component signals, but I suspect a late Sony CRT probably has better circuitry for that than you could likely build, so I'd say try s-video.

So the only complicated bit is reflashing the OS when you can't see what you're doing. I have a boot.scr file from somewhere that I can probably find if you really need it. Put the OS files on a small partition on a known good bootable SD card (anything small or by Sandisc primarily), insert in the left SD slot, bring the unit up and see what happens. I think the left SD light should flicker, but don't quote me on that. If you have a pandora data card (with pandora/appdata on it) and put that in the right slot, you can watch for the right SD slot to make sure it's not reading that which would indicate it's booting normally into the OS and you need to try again. I forget if you need to hold down the R button when powering up.

Edit: Oh, you say that TV doesn't have s-video in? That's unusual. Yes, then you'd need to split the s-video C signal into it's discrete Pr and Pb signals. You'll have to look up the s-video specs to be sure, but I think the Y signal is on one of the pins unencumbered, so you should be able to get a black and white signal out just with the right sockets plumbed together. In terms of splitting the C signal, IIRC that's an analogue modulation on a carrier frequency, so your basic TV/radio tuner technology to decode. That'll be an active circuit, so you'll need a battery or something to run it.

 

[TheGrandPubaa]

Yes, this is how I've been running my Pandora for years now after I shorted out the LCD socket on my mobo and had to remove it. When you reflash you unit, TV out will be on by default (although probably in composite mode and hopefully 480i), and from there you can set it to output in s-video (s-video is pretty damn good for a 480i signal - it's a lot better than composite). You can split s-video out into its component signals, but I suspect a late Sony CRT probably has better circuitry for that than you could likely build, so I'd say try s-video.

So the only complicated bit is reflashing the OS when you can't see what you're doing. I have a boot.scr file from somewhere that I can probably find if you really need it. Put the OS files on a small partition on a known good bootable SD card (anything small or by Sandisc primarily), insert in the left SD slot, bring the unit up and see what happens. I think the left SD light should flicker, but don't quote me on that. If you have a pandora data card (with pandora/appdata on it) and put that in the right slot, you can watch for the right SD slot to make sure it's not reading that which would indicate it's booting normally into the OS and you need to try again. I forget if you need to hold down the R button when powering up.

Edit: Oh, you say that TV doesn't have s-video in? That's unusual. Yes, then you'd need to split the s-video C signal into it's discrete Pr and Pb signals. You'll have to look up the s-video specs to be sure, but I think the Y signal is on one of the pins unencumbered, so you should be able to get a black and white signal out just with the right sockets plumbed together. In terms of splitting the C signal, IIRC that's an analogue modulation on a carrier frequency, so your basic TV/radio tuner technology to decode. That'll be an active circuit, so you'll need a battery or something to run it.

Thanks for the quick reply. So there may not be a clean/simple solution for getting the YPbPr without some engineering? That's unfortunate and probably beyond my means, although it may behoove me to get the cable to use the composite at least for the time being.

About reflashing, I could potentially just install Angstrom onto the SD card and run it from there, right? That might be a simpler solution initially, though it has been years since I played around with installing an OS to the SD and running it.

 

[levi]

Yes, first stage is getting a composite output working I suspect. Then getting a monochrome Y signal from the S-video output, which should at least be sharper. To my mind, building a working bootable SD card is harder than booting the reflasher. I did used to run my OS from an SD card, but then I decided that the NAND was almost certainly going to outlive my use of it, so I reflashed that and have been opkg updating ever since, pretty much (apart from one solid reflash to get the improved SD card booting handling introduced a few OS versions ago, although since I have SD cards that work anyway, that was kind of unnecessary for me).

 

[TheGrandPubaa]

I'll have to do some reading on that. My other issue is that the battery is kind of bulging and doesn't seem like a good long-term solution to use inside the Pandora, but I can't remember if it is possible to power the unit(with a PSP charger) without having the battery installed. If I am going to use this on a TV, obviously a battery doesn't need to be in it constantly charging.

Edit: I just tried it with the PSP charger and the green light did, indeed, turn on. So hopefully I can take that to mean that power shouldn't be an issue.

 

[sm0kew0n]

Batteries are quite inexpensive at the moment - https://www.dragonbox.de/en/53-pandora-replacement-battery-1.html

 

[TheGrandPubaa]

Last time the LCD worked, my Pandora's OS on the NAND was functional. I wonder if it would be easier - potentially - to enable TV-Out blindly using the Pandora button and the DPAD/Buttons. Perhaps somebody could jot down a list of the buttons to press to get a minimal composite display to at least get something on the TV?

 

[levi]

This AVforums thread (http://www.avsforum.com/forum/37-video-processors/1389459-diy-s-video-component-converter.html) ends up suggesting the best way to to get a consumer converter, but also mentions a few TV chips you can use to demodulate the Pb and Pr out of the C (chroma) pin.

I may be wrong, but I don't think you can enable TV out using the keyboard - the settings applet is mouse driven only. You could always spawn a terminal and invoke the right script under /usr/pandora/scripts (probably op_tvout.sh, but I don't have my unit on to test at the moment). IIRC to get a terminal up blindly it's pandora button, then down, down, enter.

I'm not sure how much current a Pandora running off the charger port will take. Mine doesn't boot at all without a battery, but I understand more non-GHz units work better without a battery. If you turn everyone on and attach hungry devices to the ports, it might cut out on you though, since as far as I know you're relying on an undocumented function.