Modified CGA to VGA Scaler to accept clean sync RGB SCART

[fagin]

Doesn't the CPO allow you to set the sync polarity in the menu ?

Nope.... only V2 allows that.

[bencao74]

Hey,

I`ve started to port the work of fagin to a design. Take a peek here. Current working name is "Sync Strike".

http://bencao74.blogspot.com/2011/02/sy ... rator.html


http://2.bp.blogspot.com/-JrrKUNsaj7Q/T ... strike.png

So this is a preliminary release. I`ve some work todo because SailorSat gave me some hints how to achieve real Hsync. And I`m not quite sure about the power supply. I`ve tried to integrate "the power supply" from scart pin 8. Here something up to 12V is coming. I`ve put a 7805 inline to harmonize the current level. I`m sure there exists better solutions.

[ckong]

Hey,

I`ve started to port the work of fagin to a design. Take a peek here. Current working name is "Sync Strike".

http://bencao74.blogspot.com/2011/02/sy ... rator.html

Can't wait to see where this leads to.

This would be very great, a nice little professional looking PCB doing the trick, no loose wires and other messy (soldering) stuff anymore.

[Fudoh]

If you don't want to limit the sync strike to tri-sync arcade monitors, you should include a dip switch to choose between H/V sync anc composite sync on the H-pin for the HD15 output. There are enough applications which require clean c-sync instead of seperate sync lines and it would be a shame if the HD15 output couldn't be used for those.

[emphatic]

Awesome!

[bencao74]

If you don't want to limit the sync strike to tri-sync arcade monitors, you should include a dip switch to choose between H/V sync anc composite sync on the H-pin for the HD15 output. There are enough applications which require clean c-sync instead of seperate sync lines and it would be a shame if the HD15 output couldn't be used for those.

Oh, great info!! exactly need this kind of input! Thanks fudoh

[Zapf]

What is the latency on the cga-vga scaler?

[Trevor spencer]

Very nice

[Almighty]

awesome!

i will wait before i buy a XRGB device to connect my Super Famicom on my LCD, with this and the SLG-3000 i think/hope this will be working perfect

[bencao74]

just designing here some stuff and was pointed on this project.



What is the motivation behind the Vsync on and off switch?

[Fudoh]

Doesn't seem to be neccessary. I could imagine that it's a safety switch for devices which get confused if composite sync is available on the H-Sync pin and V-Sync's present on the V-Sync pin.

[bencao74]

okay then ...

I`ve made some further design on sync strike.

Features
- reverse polarity protection
- screw terminals 5mm for external PSU (5V to 12V)
- RCA jacks for Audio
- Scart RGB in
- Female VGA 15Khz out with clean sync signals for RGBHV
- Switch for RGB and CSYNC on HSYNC line. Thus this device is not limited to trisync monitors. (thanks fudoh)
- Switch between external PSU and possible power supply on SCART
- Screw Terminals 5mm for all signal RGB, HSYNC, VSYNC, CSYNC and AUDIO
- Real HSYNC (thanks sailorsat)
- Mounting holes



So this project will be included in the pcb order

[ckong]

okay then ...
So this project will be included in the pcb order

sounds great, but what do you mean with pcb order?

[emphatic]

okay then ...
So this project will be included in the pcb order

sounds great, but what do you mean with pcb order?

Surely all other arcadeforge PCB products.

[ckong]

Ah, of course. Stupid me.

[Trevor spencer]

Ill be interested in one of these when there released , Will have also have a nice case ?

Love little gadgets like this

[Almighty]

Ill be interested in one of these when there released , Will have also have a nice case ?

Love little gadgets like this

Amen

Would be perfect in a nice case, safe and clean and offcourse for the looks

Put me also on the list, just need one for my superfamicom/Megadrive.

[xavierjesus]

Same here, if this ever happens (a la SLG3000), put me down for one!

I seriously need an idiot proof RGB scart -> VGA device, at this end of affordability.

Bring on the SLG3000 scanline sweetness/LCD monitor, for me ol' consoles & supergun.

Yessirr!

[fagin]

Same here, if this ever happens (a la SLG3000), put me down for one!

I seriously need an idiot proof RGB scart -> VGA device, at this end of affordability.

Bring on the SLG3000 scanline sweetness/LCD monitor, for me ol' consoles & supergun.

Yessirr!

The bits cost less than £5 to make the circuit etc and it is easy as I did it! Lol. However I can understand that you want to buy something ready built, and Jochens solution will be just the ticket!

[bencao74]

yes, I`ve to count my other PCBs (Dual Strike, MAK Strike, SLG, ...), perhaps add another project and then I`m ordeing again. This really fun. I`m always very exited ordering about 100 or more pieces of possible scrap / cat food.

When this SYNC Strike works fine I`m adding a case like the SLG style.

[fagin]

yes, I`ve to count my other PCBs (Dual Strike, MAK Strike, SLG, ...), perhaps add another project and then I`m ordeing again. This really fun. I`m always very exited ordering about 100 or more pieces of possible scrap / cat food.

When this SYNC Strike works fine I`m adding a case like the SLG style.

Let us all know when these kits are in production mate. I have a number of people asking me via my YouTube video's on a ready made solution such as yours, to work with the CGA > VGA scaler option.

If you want to send a review version over to me, I can do a connection and review vid on YouTube about it!

[headlesshobbs]

I'm curious. For some of the consoles YUV is the only route... does there happen to be a way of downconverting back to RGB?

[Fudoh]

For some of the consoles YUV is the only route...

which systems would that be ?

Also the CGA to VGA Scaler has got component inputs as well, so why would you want to convert back to RGB first ?

[fagin]

Just to clarify and assuming the CGA to VGA scaler has been modified using either my method or bencao74's solution, you will have:

Input
YUV (480i, 576i, 720i, 1080i, 480p, 576p, 720p, 1080p)
RGB SCART - via mod to RGBs Header
DSUB15 - CGA / EGA RGBHV
JAMMA - CGA / EGA
8pin Header for RGBs input

Output
31khz DSUB15 (31k @ 640*480, 800*600, 1024*768, 1360*768) x2
12pin VGA Header (x2)

[headlesshobbs]

For some of the consoles YUV is the only route...

which systems would that be ?

Also the CGA to VGA Scaler has got component inputs as well, so why would you want to convert back to RGB first ?

The main ones I'm looking at here are Gamecube and Xbox. They didn't manufacture them with 15hz in mind.

[Fudoh]

The main ones I'm looking at here are Gamecube and Xbox. They didn't manufacture them with 15hz in mind.

you can both of these connect directly to the CGA to VGA Scaler. As long as the output on the scaler is set to 480p as well it will act as an transcoder - should be fine. If you're looking for a standalone transcoder instead (XBox -> transcoder -> SLG3000) look at the PSP Scaler from Lenkeng (LKV-7000).

[bryan_c]

Does anyone have any numbers on how laggy the CGA to VGA scaler is with 240p, 480i, and 480p sources?

I did find a review of what looks to be the same scaler (GBS-8220) claiming that it's lag free in Beatmania IIDX (which I believe runs in 480i)... But I've read elsewhere that the HDBoxPro can introduce about 3 frames of lag, and the CGA to VGA scaler is an HDBoxPro clone so it would be reasonable to expect it to perform similarly. So, which is it?

fagin, would you mind comparing the CGA to VGA scaler's lag vs. that of your shiny new DVDO Edge? I'd really appreciate it!

[fagin]

If someone tells me how to measure this precisely.

[autopilot]

What would happen if you didn't use this LM1881 circuit?

I've been trying to connect an original xbox and ps2 via scart cable to the RGBS input on the same scaler board and output to a VGA monitor. With both consoles, it displays the boot screen fine on the monitor but when it loads a game or application the scaler board says "No signal". Would that additional circuit solve the problem?

thanks

[bryan_c]

I've never actually measured input lag myself, so take the following with a grain or three of salt. From what I understand it unfortunately seems rather difficult to get precise measurements. I'd imagine others on this board would know much more about getting good measurements than I do. With that out of the way...

It would be best to compare with a display that's known to have little or no lag, like many (all?) CRTs.

The least precise way would just be to compare how both feel. Obviously this is totally subjective! But it's trivial to do, and large differences in latency will be pretty apparent to anyone at all sensitive to lag. (This was actually all I was expecting when I asked you by name, fagin... on rereading, I guess it looks a bit like I was asking you for measurements, when I instead intended to ask the separate questions "does anyone have precise numbers" and "fagin could you eyeball it against your nearly lag-free scaler, since you have both". Sorry if I sounded demanding... But if you could be bothered to try for something more precise that would be great! )

For a bit more accuracy, you could try the 240p test suite. This is another thing I haven't tried myself, but according to the wiki page there's a lag test that beeps in time with a visual cue. If you try this, don't route the sound through the Edge, as I've read that it delays sound to match its current picture delay. You could try recording the test with a video camera, and see how far apart the frames with the visual and aural cues are... though this presumes your camera's video and audio are perfectly in sync, and even then the results would have error bounds based on your camera's framerate (lower = less accurate). If you're really accurate at timing button presses you can try to press it in time with the cues, and the test will display an average, but this is again subjective (but less so if you have good timing).

Some rhythm games have lag testers. Rock Band 2 can measure lag using the guitar and microphone with no user input (source), though I don't know how accurate it is.

Many consoles can display the same picture on several outputs simultaneously, though often this would mean modding a video cable so that the pins for multiple outputs are connected. You could try (for instance) running svideo to the Edge, and RGB to the CGA to VGA, from the same console at once, to two displays, and see if one lags more than the other. This assumes that both outputs on the console are equally laggy (probably true), and that both displays are equally laggy (less likely). Again, you could record this and try to count how many frames one is behind the other, but the same concern about camera framerate applies (though you wouldn't need sound in this case).

Benjamin Heckendorn has created a few modified controllers that light up LEDs when various buttons are pressed. The idea is that you press a button and use a high speed camera to count how many frames pass between the LED light-up and an on-screen reaction. The same disclaimer about camera framerate applies. You likely wouldn't want to buy one of Ben's for this purpose as they're quite expensive and only produced for consoles that (I believe) don't support 240p. So I guess you'd have to mod a controller for this, though you'd only really need one button for testing scaler lag...

Any tests you're willing to do would be appreciated. I'm trying to decide on a scaler; I don't think I'd mind the video quality of the CGA to VGA as long as I pair it up with an SLG3000, but if it has high latency it would be a deal breaker for me.