Component Video Hat

tjohnson

Looks an interesting project, I thought the gert used a resistor ladder while your solution looks to be using some sort of IC / processor to process the analogue signal?

I've been able to get a nice 240p output using an HDMI to VGA converter and then built a homemade VGA to scart cable with a couple of resistors to combine the horizontal and vertical sync signals into one. Works well, I've had to enable overscanning to bring the image into the edges of the TV. looks 100% genuine arcade quality on my JVC CRT television.

I've tried the 240p beta firmware which also works, I found the 50hz PAL option better quality than the 60hz NTSC option which had more of the rainbow effect which you get with composite but it had none of the horrible flicker of interlaced 480i.

mikechi2

@maxriptide Sweet, thanks! I got the pixel scaling correct.. now need to get the hdmi_timings. Hope I don't have to go to work to use the scope...

mikechi2

@tjohnson The idea is indeed the same as Gert -- the ICs are amplifiers are for mixing the RGB -> Component. Also there's a voltage regulator; I don't trust the PI to have clean outputs on the GPIOs.

For the next gen, I was thinking of using a real triple video DAC but it looks like they're quite pricey. A R2R ladder would be better though, the problem with the current design is the need for binary scaled resistors which are also hard to find over a range of 8 decades.

mikechi2

@IcyFever Haha, thanks! If I ever get there you'll be the first to know! Yeah, I really lucked out - found one on Craigslist yesterday for $30. I didn't even know about the FV310 until you mentioned it. I used to have an older WEGA but the FV310 really surprised me on how sharp it was.

mikechi2

Hi Guys,

Here's an update. Thanks again for all your help and kind comments! I figured out all the scaling issues and everything works nicely. I'm as happy as a cat :)

Also designed generation 2:

alt text

It should solve the noise problems, be easier to build and adds a NTSC encoder for S-Video and composite outputs!

mikoy

looking forward to this! just amazing, this is everything i ever wanted.

edmaul69

@mikechi2 not sure why i never saw this thread. I am very much i terested. As long as i dont have to do any programming i am ok with assembling it myself if it makes it easier for you. I have been obsessing about going crt lately. Since you mentioned a scope, i also decided to build a circuit to use one of my scopes as a tv. Just because i can. :)

mikechi2

Thanks guys :) The next gen is done. It adds S-Video (which looks awesome and really makes it compatible with most higher end TVs) as well as composite (which is crap):

Still need to shoot down some bugs. In the meantime, I might also suggest checking this out to get your 240p (via composite) fix:

https://retropie.org.uk/forum/post/60639

Will keep you posted!

edmaul69

@mikechi2 im going to need to buy some some video cables for my pi-station 1. I have the original video port still for composite. Now i am going to have to wire s-video and component to it as well. :) 😊

mikechi2

@IcyFever @edmaul69 @mikoy

Thanks everyone, check out my site for more info: www.retrotink.com

edmaul69

@mikechi2 can you post what settings we need to set/add in the config.txt or anything else we need to change to get this to output video?

mikechi2

@edmaul69 Good question. Argh, I don't have permission to upload a file. I'll post detailed instructions on the website this weekend along with some notes about how I'm configuring my emulator settings and get back to you ASAP!

edmaul69

@mikechi2 awesome. Thank you.

mikechi2

@edmaul69 Updated the website with some instructions!. Will keep updating - there's rapid progress in the community towards better tweaking and optimizing the settings.

Rion

@mikechi2 Hi mike! Any news about RetroTINK-ULTIMATE?