Sync on green devices that output 15khz (240p/480i)?

[Fusion916]

Which devices output using sync on green at 15khz? I have a PS2 but it only outputs sync on green at 480p in RGB mode.

[nmalinoski]

In the context of video game consoles, nothing, to my knowledge, outputs 15kHz RGsB. The only way you'd get it is if you ran RGBS output from any 15kHz console into an Extron RGB interface configured for RGsB output.

And, on that note, the PS2 is the only games console I'm aware of that outputs RGsB in the first place; usually better to use an RGB interface or something similar to convert the PS2's RGsB output to RGBS, or mod the console for full-time RGBS. (Or wait for an HDMI mod to come out.)

[energizerfellow‌]

You're better of running the PS2 in YPbPr component mode anyways as all resolutions will run over YPbPr while looking just as good, plus you'll need to deal with YPbPr anyways if you have a PSP, Wii, or OG Xbox. There's also component for running your GCN/WiiU/PS3/360 over analog.

[Fusion916]

This is not for me personally, its for a new product I'm developing, I just need it for testing.

Is there really *no* video game console, even some obscure ones, that don't do sync on green at 15khz? That is very surprising as I get the sync on green question quite often.

[energizerfellow‌]

Yep, just the PS2 in the gaming world. SoG was a Sony standard back in the day. Even in the classic PC space, Silicon Graphics and Sun workstations were the only SoG users I can think of off the top of my head. Supposedly there's a decent amount of SoG for older medical imaging equipment.

If you need a list of games:
https://playstationdev.wiki/ps2devwiki/ ... play_Modes

[nmalinoski]

This is not for me personally, its for a new product I'm developing, I just need it for testing.

Is there really *no* video game console, even some obscure ones, that don't do sync on green at 15khz? That is very surprising as I get the sync on green question quite often.

Well, honestly, there's no reason for any console to output 15kHz RGsB, because 15kHz RGB, at least when it comes to consoles, was used with SCART, which is RGBS (with composite video as sync). The cables and some SCART hardware are capable of 480p+, but it's uncommon, because sending 480p to an SD-only display can supposedly damage it. (That's probably why the PS2 switches to RGsB, which results in no sync signal over SCART, and why the Xbox doesn't allow 480p+ over SCART at all.)

Overall, I think sync-on-green is kind of an edge case, because it really is only the PS2 that uses it, and only for 480p+, and only when using RGB output--the Xbox, GameCube, and most everything else newer used either YPbPr component or some form of RGBHV for analogue 480p+.

RGsB is a hassle for a handful of reasons:

• First, and probably most glaring, is that SCART equipment doesn't like it, because SCART relies on an external sync signal, and the two sources a PS2 provides for external sync--composite video and luma--get shut off when the console switches to RGsB.
• Second, my understanding is that at least the Framemeister does not work with RGsB sources; it requires RGBS.
• Third, in order to work with SCART and other RGBS/RGBHV equipment, you need an RGB interface, like those made by Extron, which means you now need a custom-made PS2-to-DE-15 cable (with an audio breakout if you're not going to use TOSLINK), and then a custom BNC-to-SCART/VGA/etc. cable to use the resulting RGBS/RGBHV with your other equipment.
• And, lastly, until recently, if you wanted to use 480p+ via an OSSC, which does support both RGBS and RGsB, you would have to continually switch between RGsB and RGBS if you were playing a game like Gran Turismo 4, which switches back to 480i for menus and prerendered cutscenes.

In my opinion, there are no real good solutions at the moment for handling RGsB from the PS2; the Extron equipment is getting old, rare, and expensive, not to mention the cost of the cabling or SCART equipment in general.

In lieu of an HDMI mod (Which would honestly be my preference; not to be confused with the garbage HDMI dongles and cables that just digitize the RGB or YPbPr), and for those that want to integrate their PS2 into their RGB SCART setups, what I'd really like to see is something along the lines of the Behar Bros. Toro that would automatically interpret RGBS and RGsB to provide full-time RGBS output with clean, 75Ohm composite sync via SCART and/or full-time selectable RGBS or RGBHV with TTL sync via DE-15. No real need for the other features on the Toro, like the scanline generator or brightness toggle.

[theclaw]

PS3 also uses RGsB, if even less useful. The OS setting restricts it to 480p (or 576p).

[rama]

Maybe it's possible to use homebrew software for the PS2 that can force RGsB on other video modes.
GS Mode Selector already has the framework to attempt it.
SOG could be a bit that needs to be toggled, but I don't know where to find it.

Another way could be to hook up a microcontroller to the video encoder I2C bus.
I did this once and discovered some commands that change how the encoder works.
I didn't follow it through further though, and GS Mode Selector might be an easier way to achieve the same.

Code: Select all

// valid commands SCPH-50004(DVE):
// 0x30 pal / ntsc subcarrier? and pedestal level
// 0x37 toggles green tint
// 0x3F result = 0x35
// 0x40 sets brightness (or contrast)
// 0x41 LSD trip + makes RGB green tinted (macrovision stuff)
// 0x42 odd return value: FFFFFFFA
// 0x43 only composite: rainbow colors. result = 0x35
// 0x44 sets brightness (or contrast)
// 0x45 rainbow colors result = FFFFFF95
// 0x46 sets brightness (or contrast) result = 5
// 0x47 only composite: different kind of brightness result = FFFFFF95
// 0x48 sets brightness (or contrast)
// 0x49 composite: messes up subcarrier RGB: slightly jumpy
// 0x4A looks like some kind of brightness adjust
// 0x4B composite: LSD trip RGB: jumpy
// 0x4C only composite: slightly moves picture horizontaly result = FFFFFFFF
// 0x50 wiggles picture horizontaly
// 0x51 LSD Trip
// 0x52 anything other than parameter = 0 > black screen no sync
// long time nothing..
// 0x7D no pic change but return value changes to 0x1C
// 0x87 only composite: toggles small flickering bar on bottom of screen

// valid commands SCPH-30004(AVE+DVE):
// 0x60 something colorburst (on / off?)
// 0x62 different modes, one causes rolling picture. could be macrovision?
// 0x70 something interlace mode on / off
// 0x72 seems to be color burst phase!
// 0x76 does something every couple values
// 0x7A image shift horizontally (tested in DVD mode)
// 0x7D image shift vertically up (tested in DVD mode)
// 0x7E image shift vertically down(tested in DVD mode)
// 0x91 timing > black screen every couple bits
// 0x93 something clock?

[Classicgamer]

Any console with rgb out can be made to sync on green with the right cable and know-how.

Any machine that outputs sync on green can be made to output RGBs (or RGBHV) with a cheap sync seperator circuit ($10- $15 on eBay) or an Extron rgb interface (also $15 on eBay).

If you look at the retro gaming cables website, you'll notice that they offer PS2 cables wired for both SOG and RGBs. They incorporate sync seperators into the cables to achieve this.

Dealing with SOG is really not a big deal but I'm not really clear on what the issue is here. What are you trying to achieve?

Either way, Extron RGB interfaces solve all sync related issues and are still very cheap and plentiful on ebay.

BTW, Scart is not a standard (like VGA). It's just a plug type (like BNC connectors). A scart plug can be wired with any signal the display can handle through it's scart port. Not all scart ports can handle RGB (of any sort). They can be used for SVideo or composite video etc).

[nmalinoski]

BTW, Scart is not a standard (like VGA). It's just a plug type (like BNC connectors).

SCART and VGA are both standards. The difference is that SCART is specifically a cabling standard that was designed to carry composite, S-Video, and RGB, along with stereo analogue audio; while "VGA" could refer to a connector standard, a video mode standard, or the 640x480 resolution.

[Classicgamer]

BTW, Scart is not a standard (like VGA). It's just a plug type (like BNC connectors).

SCART and VGA are both standards. The difference is that SCART is specifically a cabling standard that was designed to carry composite, S-Video, and RGB, along with stereo analogue audio; while "VGA" could refer to a connector standard, a video mode standard, or the 640x480 resolution.

No it isn't. VGA is a standard because it specifically means an RGBHV signal running at 480p through a DB15 cable. It was a specific mode on IBM compatible computers.

There is no scart standard. A scart plug can be wired for any type of signal. I owned many TVs and monitors with scart ports when I lived in the UK. Many had multiple ports and often had some that were not wired for RGB. Some later models were even wired to accept component through the scart port. Some scart TV's could run in 50 or 60hz. Some could only do 50hz. Some were NTSC compatible. Many were not. There was no scart standard.

Scart is usually used for 480i / 240p but it can be used for any resolution you could use a db15 cable for. You can have a scart to DB15 cable that works with no transcoder of scaling hardware. I have one.

The Euro connector (aka scart plug) was designed as a universal plug to allow compatibility of AV equiptment across European countries which mostly all ran on Pal or SECAM but with different RF connectors. It was not economical to make different hardware for every (small) European country.

This also explains why Europe and Asia got RGB ports and America didn't. It wasn't that Sony and Toshiba got together and decided that Americans didn't deserve it or couldn't appreciate it. The North American market was just large enough to warrant it's own VHS and laserdisc models.

[Xer Xian]

Hdmi can carry lots of different timings and at least two video signals (rgb and ycbcr) at various color depths. Some hdmi ports on some devices are limited to only a few of the possible combinations.

Does this mean hdmi is not a standard?

[maxtherabbit]

Hdmi can carry lots of different timings and at least two video signals (rgb and ycbcr) at various color depths. Some hdmi ports on some devices are limited to only a few of the possible combinations.

Does this mean hdmi is not a standard?

I was trying to think of the appropriate respond to the previous post without resorting to "lol wut" or going over the top.

I think you said it perfectly, well done

[Classicgamer]

Hdmi can carry lots of different timings and at least two video signals (rgb and ycbcr) at various color depths. Some hdmi ports on some devices are limited to only a few of the possible combinations.

Does this mean hdmi is not a standard?

It isn't a standard like vga or cga with a stated resolution although there is a standard of sorts for digital rgb (often referred to as DVI-D) and every HDMI and DVI-D port adheres to it . There has to be for digital encryption among other things. DB15, DB25, scart, BNC connectors are all plug types that can (and are) used for any analog signal.

There isn't a single device with HDMI ports or DVI D ports that is not compatible with that digital rgb color space though. If you bought a monitor with HDMI ports and it didn't work with the digital rgb output from your GPU or Blu Ray's HDMI or DVI-D port, you would take it back.

On the other hand, there are plenty of Tv's with scart ports or BNC connectors that are not wired for RGB. It is not a requirement as there is no standard called "scart" or "BNC".

Saying something is "scart compatible" tells you nothing except that is has a 21 pin Euro connector. Saying that a monitor is cga and VGA compatible tells you that it accepts RGB HV and RGBS in 15khz and 31khz. Saying "HDMI compatible" tells you it accepts a digital RGB signal as a minimum. That is what a standard is.

[nmalinoski]

Cables can be standards, too.

[theclaw]

Doesn't scart have to support rgb and/or composite?
It's very likely a TV's scart that isn't wired for rgb, will accept composite.

At least I've never heard of a TV sold with a scart input incapable of either.

[nmalinoski]

Doesn't scart have to support rgb and/or composite?
It's very likely a TV's scart that isn't wired for rgb, will accept composite.

At least I've never heard of a TV sold with a scart input incapable of either.

S-Video, too; and both composite and S-video can be sent both ways.

[theclaw]

Doesn't scart have to support rgb and/or composite?
It's very likely a TV's scart that isn't wired for rgb, will accept composite.

At least I've never heard of a TV sold with a scart input incapable of either.

S-Video, too; and both composite and S-video can be sent both ways.

Well s-video appeared a few years later, and wasn't especially popular in regions that already had scart.

[Fudoh]

On European Scart composite video is the required minimum. VHS VCRs with Scart output (common over here) output that. Everything else was optional. RGB was common (while not granted). S-Video is rarer, since it conflicts with RGB (s-video chroma is wired to the "R" RGB pin) and needs a digital selection if it's available on the same scart input.

Japanese RGB21 on the other hand didn't require composite (or even support it?).

And then there was the story of Scart in France, where it has been used to bypass the Secam limitations. With Secam being a rarely available standard, it was sometimes easier to offer PAL converted to RGB instead of offering native Secam support (think of the french NES).

[Classicgamer]

On European Scart composite video is the required minimum. VHS VCRs with Scart output (common over here) output that. Everything else was optional. RGB was common (while not granted). S-Video is rarer, since it conflicts with RGB (s-video chroma is wired to the "R" RGB pin) and needs a digital selection if it's available on the same scart input.

Japanese RGB21 on the other hand didn't require composite (or even support it?).

And then there was the story of Scart in France, where it has been used to bypass the Secam limitations. With Secam being a rarely available standard, it was sometimes easier to offer PAL converted to RGB instead of offering native Secam support (think of the french NES).

That is exactly right.

There has never been a standard for what scart had to be wired for. It's just a plug type like BNC connectors or db15.

When I lived in the U.K., it was a common enough discussion in gaming publications on which tv's had scart sockets that could accept both the RGB color space and a 60hz signal.

My dad was a real cheapskate and always bought these cheap Eastern European TVs instead of investing in a nice Trinitron. Some had scart but no RGB. Some had RGB but only accepted 50hz. One, frustratingly accepted RGB but was only compatible with NTSC 4.43 instead real 3.58 so it converted my SNES and Neo Geo games to letterbox format...

A standard would have been great but it never happened. The advice at the time was to stick to Japanese brands, Sony, Toshiba, Panasonic etc as they usually had 60hz rgb.

[Classicgamer]

Doesn't scart have to support rgb and/or composite?
It's very likely a TV's scart that isn't wired for rgb, will accept composite.

At least I've never heard of a TV sold with a scart input incapable of either.

S-Video, too; and both composite and S-video can be sent both ways.

Well s-video appeared a few years later, and wasn't especially popular in regions that already had scart.

Every Sony TV I owned in the UK had scart, SVideo and composite video ports. SVideo and composite were commonly used with video cameras so the ports were at the front under the pull down flap.

We had an NEC tv that had SVideo but no scart port too.

My memory from the early to mid 90's was that hardly anyone knew anything about the different ports on the back of their tv's. People in TV shops gave blank looks when you asked if a model had RGB 60hz scart. I knew about it because I bought American and Japanese consoles. My friend in France knew about it because he didn't like his porn being in black and white. Nobody else that I knew could explain what scart or SVideo was used for.