Stop ragging on SCART!

The place for all discussion on gaming hardware
SuperSpongo
Posts: 314
Joined: Sat Mar 17, 2018 2:49 pm
Location: Germany

Re: Stop ragging on SCART!

Post by SuperSpongo »

Because the "VGA standard" (if that's the right word here) loosely defines pin 9 as 5V. A lot of cables are missing this pin entirely, I think because its function was redefined over the years.

So yeah, it would be interesting to know if the Extron switches pass it through carrying 5V.
User avatar
Sumez
Posts: 8010
Joined: Fri Feb 18, 2011 10:11 am
Location: Denmarku
Contact:

Re: Stop ragging on SCART!

Post by Sumez »

Interesting. I definitely didn't know about that. Don't think I've seen it on any pinouts.
strayan wrote: Why destroy a perfectly good VGA cable when you could just use it?
I don't think VGA cables are in any real limited supply.
SuperSpongo
Posts: 314
Joined: Sat Mar 17, 2018 2:49 pm
Location: Germany

Re: Stop ragging on SCART!

Post by SuperSpongo »

strayan wrote: Why destroy a perfectly good VGA cable when you could just use it?
Again, because it looks cleaner and I dont have to buy an expensive custom plug with three other plugs sticking out of it.
strayan
Posts: 671
Joined: Sun Mar 19, 2017 8:33 pm

Re: Stop ragging on SCART!

Post by strayan »

Sumez wrote:Why pin 9?
Because that’s the pin the voltage is on.
strayan
Posts: 671
Joined: Sun Mar 19, 2017 8:33 pm

Re: Stop ragging on SCART!

Post by strayan »

SuperSpongo wrote: Again, because it looks cleaner and I dont have to buy an expensive custom plug with three other plugs sticking out of it.
Two. It’s powered on pin 9.
SuperSpongo
Posts: 314
Joined: Sat Mar 17, 2018 2:49 pm
Location: Germany

Re: Stop ragging on SCART!

Post by SuperSpongo »

That is, if your VGA source provides 5V on pin 9.
fernan1234
Posts: 2167
Joined: Mon Aug 14, 2017 8:34 pm

Re: Stop ragging on SCART!

Post by fernan1234 »

On the Extron VGA Ars (which is the only switch with auto-switching option by Extron that I know, but there may be others that switch via a different mechanism), you can check the manual to see if there are any details, but I recall something to the effect of it simply detecting the latest active signal and switching to that. I know it auto-switches even with a YPbPr signal, so it doesn't only switch by detecting H or H/V on the usual sync pins. Actually I just remembered it even also switches by detecting only a signal on the audio line without any video signals on the VGA pins!
User avatar
matt
Posts: 567
Joined: Mon May 09, 2005 5:46 am
Location: Honolulu, Hawaii

Re: Stop ragging on SCART!

Post by matt »

Sumez wrote:Why pin 9?

I'd assume an Extron switch just switches everything on the DB15 ports, I guess the question is whether it does so indiscriminately?
Like, could you literally wire any signal (within reasonable voltage) to either of the 15 pins, and it would be switched out in the same manner for the output connector, or does it treat each signal for what it is, treat all the ground pins as a single signal, or common ground across all the inputs, etc.?

It does at least seem to have some sort of mechanism for detecting an active signal in any of the inputs for auto switching.
I've never tried connecting anything to pin 9 on one of my extron switchers, but I'm pretty sure they only pass the RGBHV pins. I've tried shuffling the signals around to some of the ID pins and it didn't work.
User avatar
Sumez
Posts: 8010
Joined: Fri Feb 18, 2011 10:11 am
Location: Denmarku
Contact:

Re: Stop ragging on SCART!

Post by Sumez »

That's good to know.
I could still easily output 5v on pin 9 though, completely independent from what's on the input.
neorichieb1971
Posts: 7666
Joined: Wed Jan 26, 2005 1:28 am
Location: Bedford, UK
Contact:

Re: Stop ragging on SCART!

Post by neorichieb1971 »

It was a simple cable until you Americans got involved :lol: :shock: :wink:

The more we understood about the cable, the more options that became available. SCART is in a better place than it once was honestly.

Back in 1995 I actually bought a Sony Triniton and preferred Svideo to RGB SCART on it. SCART always had a BUZZ on the audio, chopped off an inch on the right hand side of the screen with a wavey line which was ugly on Mk1 PS1's.

These days, with flat panels its a different story. You have so much fidelability (yes I made up that word) that you can make SCART a great option. Although i'd prefer 10 TV's/Monitors plugged into my consoles all the time than adding switch boxes that try to do 100 different things.
This industry has become 2 dimensional as it transcended into a 3D world.
User avatar
FinalBaton
Posts: 4461
Joined: Sun Mar 08, 2015 10:38 pm
Location: Québec City

Re: Stop ragging on SCART!

Post by FinalBaton »

One thing I just mused over, watching mike chi's live chat since he mentionned it :

TTL sync sure doesn't seem that useful to us console gamers.

What needs it outside of Extron switchers?

because most of the rest of the chain (capture cards, consumer crt) is made to work with the consumer-friendly 75ohm sync. so the typical SCART head outputting 75ohm sync, surely isn't a weakness? seems more like the sensible choice to me.

I've seen people mention that ''the standard of console cable should be to carry TTL sync'' but I'm not sure I agree.
-FM Synth & Black Metal-
mikechi2
Posts: 269
Joined: Sat Jul 01, 2017 6:56 am

Re: Stop ragging on SCART!

Post by mikechi2 »

FinalBaton wrote:One thing I just mused over, watching mike chi's live chat since he mentionned it :

TTL sync sure doesn't seem that useful to us console gamers.

What needs it outside of Extron switchers?

because most of the rest of the chain (capture cards, consumer crt) is made to work with the consumer-friendly 75ohm sync. so the typical SCART head outputting 75ohm sync, surely isn't a weakness? seems more like the sensible choice to me.

I've seen people mention that ''the standard of console cable should be to carry TTL sync'' but I'm not sure I agree.
I think the best practice is to follow the standard. So if you're using SCART, send composite video (or Luma, if the goal is cost optimization and lower cost cabling/shielding). Bad things happen when off-spec permutations start appearing.
User avatar
maxtherabbit
Posts: 1763
Joined: Mon Mar 05, 2018 4:03 pm

Re: Stop ragging on SCART!

Post by maxtherabbit »

FinalBaton wrote:One thing I just mused over, watching mike chi's live chat since he mentionned it :

TTL sync sure doesn't seem that useful to us console gamers.

What needs it outside of Extron switchers?

because most of the rest of the chain (capture cards, consumer crt) is made to work with the consumer-friendly 75ohm sync. so the typical SCART head outputting 75ohm sync, surely isn't a weakness? seems more like the sensible choice to me.

I've seen people mention that ''the standard of console cable should be to carry TTL sync'' but I'm not sure I agree.
The console uses TTL sync internally so it makes sense to output it.

Capture cards are designed for TTL, at least the Datapath cards are.

Most professional monitors don't *need* TTL sync however all of them support it. Older 15kHz RGB monitors for computer use require it. There are more extant devices that use TTL sync than not.
User avatar
FinalBaton
Posts: 4461
Joined: Sun Mar 08, 2015 10:38 pm
Location: Québec City

Re: Stop ragging on SCART!

Post by FinalBaton »

that's a good point mike and thanks for precising it.

one of my two setups uses an Extron switcher and thus requires clean sync. but I don't even know if my console cables output 75ohm csync or TTL csync. some are SCART cable going through a SyncStrike and some are console-to-DE 15 cables.

I'd have to check them and see what level of sync they output. I don't want to damage my capture card.
-FM Synth & Black Metal-
User avatar
Sumez
Posts: 8010
Joined: Fri Feb 18, 2011 10:11 am
Location: Denmarku
Contact:

Re: Stop ragging on SCART!

Post by Sumez »

FinalBaton wrote:One thing I just mused over, watching mike chi's live chat since he mentionned it :

TTL sync sure doesn't seem that useful to us console gamers.

What needs it outside of Extron switchers?
Why does a switch need TTL sync? Doesn't it just switch over the sync signal no matter how it looks?

Also, most consoles have sync on green, don't they?
Ryoandr
Posts: 269
Joined: Mon Jun 12, 2017 4:12 am

Re: Stop ragging on SCART!

Post by Ryoandr »

Sumez wrote: Why does a switch need TTL sync? Doesn't it just switch over the sync signal no matter how it looks?

Also, most consoles have sync on green, don't they?
Most switches / splitters process sync with logic chips.
I have a 4 port VGA splitter that uses a 74HC244 to distribute H and V signals to all ports, it won't work with a low level analog signal.
User avatar
bobrocks95
Posts: 3450
Joined: Mon Apr 30, 2012 2:27 am
Location: Kentucky

Re: Stop ragging on SCART!

Post by bobrocks95 »

75 ohm attenuated sync is fine for Extron switches, but it has to be clean csync, not composite video or luma.

Can't think of a single console with sync on green outside of the PS2 in 480p mode, so no clue what you're talking about there.
PS1 Disc-Based Game ID BIOS patch for MemCard Pro and SD2PSX automatic VMC switching.
User avatar
matt
Posts: 567
Joined: Mon May 09, 2005 5:46 am
Location: Honolulu, Hawaii

Re: Stop ragging on SCART!

Post by matt »

FinalBaton wrote:One thing I just mused over, watching mike chi's live chat since he mentionned it :

TTL sync sure doesn't seem that useful to us console gamers.

What needs it outside of Extron switchers?

because most of the rest of the chain (capture cards, consumer crt) is made to work with the consumer-friendly 75ohm sync. so the typical SCART head outputting 75ohm sync, surely isn't a weakness? seems more like the sensible choice to me.

I've seen people mention that ''the standard of console cable should be to carry TTL sync'' but I'm not sure I agree.
TTL sync was originally used because at the time, these consoles were meant to be used with 15khz computer monitors. These almost all used TTL level composite sync.

75 ohm level csync is an anomaly - its main purpose is to feed a pure sync signal to devices that were designed for composite video. The reason we use it now is because the SCART standard has taken over the retro gaming world, otherwise we'd likely still be using TTL for everything (as modern VGA devices still do). It's rarely been used for much else. The fact that most scalers these days require TTL sync to be attenuated doesn't seem to me like a good design choice, given that the consoles themselves were designed for a different standard.

Having said that, I've had no problems using 75 ohm level sync for most things. It works fine on all my Extron devices, and I have 3 CRT PC monitors that all work fine with attenuated composite sync even though the specs call for TTL level HV sync. It's relatively versatile.
Ryoandr
Posts: 269
Joined: Mon Jun 12, 2017 4:12 am

Re: Stop ragging on SCART!

Post by Ryoandr »

matt wrote:
75 ohm level csync is an anomaly
no it's not

Image
User avatar
Sumez
Posts: 8010
Joined: Fri Feb 18, 2011 10:11 am
Location: Denmarku
Contact:

Re: Stop ragging on SCART!

Post by Sumez »

bobrocks95 wrote:so no clue what you're talking about there.
It was a question. I don't know anything about this. For my PVM, I hooked the composite video pin of my scart adapter to the sync input on the monitor, but for some reason I thought a lot of consoles did it on green as well.

Needing to separate sync for every input going into a switch instead of only doing it on the signal coming out from it, feels like a massive waste :S Is there even any way to do that without supplying separate 5v power to each of them?
User avatar
matt
Posts: 567
Joined: Mon May 09, 2005 5:46 am
Location: Honolulu, Hawaii

Re: Stop ragging on SCART!

Post by matt »

Sumez wrote:It was a question. I don't know anything about this. For my PVM, I hooked the composite video pin of my scart adapter to the sync input on the monitor, but for some reason I thought a lot of consoles did it on green as well.

Needing to separate sync for every input going into a switch instead of only doing it on the signal coming out from it, feels like a massive waste :S Is there even any way to do that without supplying separate 5v power to each of them?
Component video is similar to SOG as far as sync is concerned (although it's a different color format), so you're not too far off the mark.

The inability to use composite for sync on Extron switchers is something of a nuisance, but most consoles either have clean sync outputs already or YPbPr. The only console where it's really necessary is the PS1, and any consoles that require a sync stripper do have +5v on the A/V port so you can just build it into the cable. It's annoying, but these switchers are such great devices that IMO it's worth the trouble.
Ryoandr wrote: Image
Yes, 75 ohm sync is a real standard but in practice hasn't been used for game consoles or many home computers. Note that the Genesis/Megadrive, which uses the CXA1145 chip, doesn't use its sync output and instead gives a rather poor quality TTL signal.
User avatar
Sumez
Posts: 8010
Joined: Fri Feb 18, 2011 10:11 am
Location: Denmarku
Contact:

Re: Stop ragging on SCART!

Post by Sumez »

any consoles that require a sync stripper do have +5v on the A/V port so you can just build it into the cable
Would it be safe to rely on that?
When I made my first adapter cable with a sync stripper, I wired up a DC plug to supply it with 5v, but I also wired it to the pin on the SCART connector to draw the power directly from there when possible. But when I hooked that up to my PC Engine (without an external power supply for the adapter), it blew the fuse on the PCE.
User avatar
maxtherabbit
Posts: 1763
Joined: Mon Mar 05, 2018 4:03 pm

Re: Stop ragging on SCART!

Post by maxtherabbit »

matt wrote:75 ohm level csync is an anomaly - its main purpose is to feed a pure sync signal to devices that were designed for composite video. The reason we use it now is because the SCART standard has taken over the retro gaming world, otherwise we'd likely still be using TTL for everything (as modern VGA devices still do). It's rarely been used for much else. The fact that most scalers these days require TTL sync to be attenuated doesn't seem to me like a good design choice, given that the consoles themselves were designed for a different standard.
This. 100%

FUCK COMPOSITE VIDEO AND ALL ITS ILK
User avatar
FinalBaton
Posts: 4461
Joined: Sun Mar 08, 2015 10:38 pm
Location: Québec City

Re: Stop ragging on SCART!

Post by FinalBaton »

Sumez wrote:Why does a switch need TTL sync? Doesn't it just switch over the sync signal no matter how it looks?
I knew Extron switches requires csync, but I was not sure if they required TTL csync or if 75ohm csync was fine as well.

but it got answered a couple posts up. looks like they work with 75ohm csync as well.

I'll test my cables, hopefuly they are all 75ohm and NOT TTL. because I plan on using them on a consumer crt.

(I feel like this might be a reason why more north americans pin for TTL : they don't have any consumer RGB crt to connect their console to so it's one reason less to require 75ohm)
-FM Synth & Black Metal-
neorichieb1971
Posts: 7666
Joined: Wed Jan 26, 2005 1:28 am
Location: Bedford, UK
Contact:

Re: Stop ragging on SCART!

Post by neorichieb1971 »

Silly question probably. What does TINK mean? Watching RetroRGB's Mike Chi interview, and any previous details on the unit or its predecessors, I've never actually learned what the TINK means.
This industry has become 2 dimensional as it transcended into a 3D world.
User avatar
FinalBaton
Posts: 4461
Joined: Sun Mar 08, 2015 10:38 pm
Location: Québec City

Re: Stop ragging on SCART!

Post by FinalBaton »

he mentionned it in the live : it's his bunny's name! haha
-FM Synth & Black Metal-
User avatar
SCARTicus
Posts: 189
Joined: Wed Apr 05, 2017 4:51 pm
Location: TX

Re: Stop ragging on SCART!

Post by SCARTicus »

maxtherabbit wrote: This. 100%

FUCK COMPOSITE VIDEO AND ALL ITS ILK
No way man!

Composite video carries an entire video signal on a single wire and is of noticeably higher quality than RF. That alone made it highly desirable for certain professional applications, such as CCTV systems, for a very long time. I work with lots of CCTV and while there are better alternatives now, CVBS still has its place in the professional world. This is largely because of a huge legacy installed base, and because it is so dang easy and cheap to work with. You would be amazed at how much it is used.
Now we have a modern single-wire professional video standard, called SDI, which travels down BNC. It's digital, and it looks fantastic compared to anything analog (except RGB). It will even do HD, with an extension of the standard called HD-SDI. But what it will not do is travel down 30-year old CCTV lines through an opera house and be reliable and usable throughout the building. With digital, you get a perfect image or nothing at all. A weak signal might cut in and out and be glitchy and unwatchable (like trying to watch an ATSC broadcast with an inadequate antenna).
With analog though, a weak, low quality signal can still be perfectly usable even if it is not pretty. You may, for example, have a conductor on stage who must be seen by an orchestra in the pit. You put a camera in front of the conductor and you send the feed down the permanently installed 75Ohm BNC runs as Composite video. That analog signal reaches the pit where you break it out to small LCD monitors clipped to the top of the musicians' music stands. This is always done the fast, cheap, easy way. Even on large Broadway-style productions and major symphony orchestras. That means lots of Y-cables and daisy chains. You end up with a very low quality image of the conductor for the musicians to see. It is noisy and ghosty, and the low-quality LCDs don't help either. But! They WILL be able to see the conductor and his hands, and his waggle stick. And that is all that is needed.
It has its place in the professional world. Still.

Oh yeah it sucks for video games and movies though.
User avatar
matt
Posts: 567
Joined: Mon May 09, 2005 5:46 am
Location: Honolulu, Hawaii

Re: Stop ragging on SCART!

Post by matt »

Sumez wrote: Would it be safe to rely on that?
When I made my first adapter cable with a sync stripper, I wired up a DC plug to supply it with 5v, but I also wired it to the pin on the SCART connector to draw the power directly from there when possible. But when I hooked that up to my PC Engine (without an external power supply for the adapter), it blew the fuse on the PCE.
Most consoles were designed to power an RF modulator through the AV port, which takes significantly more power than a sync stripper. So it ought to be OK. Not sure what your problem with the PCE would have been.
User avatar
maxtherabbit
Posts: 1763
Joined: Mon Mar 05, 2018 4:03 pm

Re: Stop ragging on SCART!

Post by maxtherabbit »

SCARTicus wrote:
maxtherabbit wrote: This. 100%

FUCK COMPOSITE VIDEO AND ALL ITS ILK
No way man!

Composite video carries an entire video signal on a single wire and is of noticeably higher quality than RF. That alone made it highly desirable for certain professional applications, such as CCTV systems, for a very long time. I work with lots of CCTV and while there are better alternatives now, CVBS still has its place in the professional world. This is largely because of a huge legacy installed base, and because it is so dang easy and cheap to work with. You would be amazed at how much it is used.
Now we have a modern single-wire professional video standard, called SDI, which travels down BNC. It's digital, and it looks fantastic compared to anything analog (except RGB). It will even do HD, with an extension of the standard called HD-SDI. But what it will not do is travel down 30-year old CCTV lines through an opera house and be reliable and usable throughout the building. With digital, you get a perfect image or nothing at all. A weak signal might cut in and out and be glitchy and unwatchable (like trying to watch an ATSC broadcast with an inadequate antenna).
With analog though, a weak, low quality signal can still be perfectly usable even if it is not pretty. You may, for example, have a conductor on stage who must be seen by an orchestra in the pit. You put a camera in front of the conductor and you send the feed down the permanently installed 75Ohm BNC runs as Composite video. That analog signal reaches the pit where you break it out to small LCD monitors clipped to the top of the musicians' music stands. This is always done the fast, cheap, easy way. Even on large Broadway-style productions and major symphony orchestras. That means lots of Y-cables and daisy chains. You end up with a very low quality image of the conductor for the musicians to see. It is noisy and ghosty, and the low-quality LCDs don't help either. But! They WILL be able to see the conductor and his hands, and his waggle stick. And that is all that is needed.
It has its place in the professional world. Still.

Oh yeah it sucks for video games and movies though.
yeah I do CCTV as well, I have no problem with it in that context

but fuck it for literally anything else
fernan1234
Posts: 2167
Joined: Mon Aug 14, 2017 8:34 pm

Re: Stop ragging on SCART!

Post by fernan1234 »

Nice post defending CVBS, SCARTicus!

I like it for the NES/Famicom. I'm probably one of a handful of people on this planet who uses an Nt Mini Noir exclusively with its composite output (okay rarely also S-video since it has the same native colors).

And SDI is actually an amazing standard. Now they're up to 12G SDI or something like that, you can deliver 8K signals with it. For SD, it can deliver the most beautiful, pristine 480i pictures (as good as analog RGB with ideal cabling at a minimum). It's a shame that SDI doesn't work with what we call "240p", at least I've never seen it working, otherwise it could have become the standard for our retro gaming also. Oh, and I guess in practice 480p would also not be doable via SDI (never seen any device that supports ED-SDI).
Post Reply