PSP on TV

[iwannamodmypsp]

I don't have a PSP yet. I know almost nothing about it. What I want to do is hook it up to a display (TV or monitor) with the highest quality possible. I do know that there are a few adapters out there that allow you to hook it up to a TV. As far as I see they convert the native video signal of the PSP into composite and s-video (which is not what I want). The question is: what is this native signal? Is there any decently sized (20"+) TV/monitor that readily accepts this signal if you just hardwire it to the PSP?

[Endymion]

Near as I can tell, these things are not converting any signal, they are cameras that are capturing the image they see as they are strapped over the PSP and creating their signal from that. How else do you think the device works without opening up the PSP, doing any modifications, etc. etc.? Why else would the thing be so huge and unweildy, strapping over the screen itself?

[Guest]

That's pretty obvious. In fact I wasn't talking about that kind of adapters but this, which clearly taps into the PSP signal and converts to composite/s-video:

http://www.lik-sang.com/news.php?artc=3723

In any case my questions aren't about adapters...

[Endymion]

I've never seen this device before, everybody seems to be hawking the others (from a few different sources no less). But, to create a signal that can be used as a Composite or Y/C line, you need to start with (wait for it) RGB. So it is entirely likely that the device you linked to has an encoder, coincidentally enough, made by Sony. Several threads on this are here already as we've seen them used as far back as the Sega Genesis for RGB boosting and composite, subsequent chips for s-video as well.

It is almost certainly working from an RGB signal. The thing to do would be to get that device and see what amp/encoder it uses, then get the pinout for it to mod it for RGB output. The PSP and the device itself are probably too small to cram a component (Y-Pb-Pr) adapter in there, so just do something to get the RGB out once you know where the lines are tapped to the chip, then you can make a component box to live outside the unit if you need to.

In any event it doesn't look like anyone has done this before, so you would be the pioneer. If they are using an encoder that you can just find a datasheet on, it should not be very difficult to do, either.

[Guest]

In fact I really hope it's some kind of RGB signal (I wouldn't even need a conversion into component since I have a scart TV) but could it be a 15khz signal? It would seem more probable to me that it's a higher res though. The converter in the link has quite a few ICs (OK, it also takes care of the controller signals) so perhaps it also downscans the frequency? Anyway Sony encoders such as CXA1145/1645 have 24 pins and I don't see any chip with the right number of pins... I can see one with 28. Other encoder chips (AD724/725) have 16 pins and there's a couple of chips on that adapter with 16 and 18 pins so who knows... most ICs appear to be scratched so part codes will be unreadable. Of course examining the adapter in person would help a lot. I just thought that someone had already looked into this matter... guess I'll have to be that someone.

[blackevilweredragon]

That mod, seems to  be capturing the LCD matrixed data, and mixing it to analog..  There is no way the PSP's LCD screen is RGB, it's all digital, sending the data in a matrixed form along the wires..  It's hard to explain, but it's digital...

[Guest]

and do you know if it's possible to get a bigger monitor that would work with the PSP? Or is it something proprietary?

[blackevilweredragon]

You could, if you can get a decoder for the PSP's LCD, to say, VGA..  (would need to be upscaled by x2, atleast that's how I would do it, because I don't think a VGA monitor can go as low as the PSP's resolution)..

As it is, VGA monitors don't truly do 320x200, the signal is sent doubled...

[Guest]

meh... I think I'm going to try to hack the PSP-TV adapter for RGB, similarly to what can be done with the GBA transverter, and hope it gives a good picture...

[blackevilweredragon]

meh... I think I'm going to try to hack the PSP-TV adapter for RGB, similarly to what can be done with the GBA transverter, and hope it gives a good picture...

It will probably give much better color, but the pixilation will still be there...

[ido8bit]

There is only digital video inside the PSP.  As it is only designed to drive it's LCD there is no need for it to generate analog video of any kind.  No monitor can be hardwired to the PSP without an adapter as there is nothing to hardwire it to.  

Unless you want to point a camera at the LCD the signal has to be converted.

As others have said it buffers the LCD signals and routes them to the docking connector.  

Inside the dock there appear to be a couple of RAM chips.  My guess is the digital signal is stored in RAM so it can be read out at TV rates before being converted to analog.  

There is analog RGB in there somewhere, you just have to find it.  That would give you an analog RGB output that would drive an RGB monitor.  For something bigger than 20" look at various Sony pro monitors, Mitsubishi Megaviews or a TV with a SCART RGB input (if you are in the right part of the world).  The resulting image would have better color than the existing composite output on the dock, but you would still suffer the scaling artifacts inherent in converting whatever the native scan rate of the PSP to 15kHz.  

For better quality you could consider bypassing the scan rate conversion and convert the digital signal from the PSP to analog.  This would give a better quality image as it would be free from scaling artifacts.  The output would now be a progressive RGB signal at whatever the PSP native scan rate is.  

This is the approach that I would take.  However, I doubt I will be getting a PSP for a long time so unless someone wants to donate a PSP and the Lik-sang kit don't expect to see me build it for a long time.

I don't know what the PSP's scan rate is.  I'm guessing that it would be below VGA (as the PSP screen is smaller than 640x480), but above TV.  If I am right there are very few monitors that will display such a signal.  I can only think of a couple of early NEC multisyncs and a few similar monitors made by other manufacturers at the time.  These are all 14" or 15" monitors.  


So while getting the best quality signal out of a PSP is possible you may
end up having to build a matching monitor if you want a screen bigger than 14" or 16:9.  

I can think of one other option.  Scale the video up further to VGA or above so that it can be displayed on a modern multisync monitor.  This may or may not look better depending on your point a view.  While it may give a sharper image it will also make pixelation more noticable than a TV unless the signal is processed even further.  

Anything is possible, but that doesn't mean it's practical or easy.

[replicashooter]

I'm interested in a mod along these lines altough I want to output the PSP signal to a different LCD.

The aim I have in mind is to create a home console based on the PSP using a PS2 pad and a larger dedicated display.

Also, if anyone has a schematic/tech sheet for the PSP2TV adaptor that was released I would appreciate a copy.

Thanks