gscartsw / gscartsw_lite / gcompsw switches support thread

[superg]

Bump, I will post a status update here shortly.

I sure hope it is an announcement of the new lite model. I have been excited to hear about that

gscartsw_lite has already been informally announced, I'm currently finalizing the design. I expect a final digikey package with some tuneup resistors today. Main feature in gscartsw_lite is digital sync regeneration. No matter how bad the input sync is, it's converted to digital, Altera detects it, calculates the timings and outputs it in a digital form which gets converted back to ANALOG and the level is properly set. Simply said it's supposed to fix all sync level issues. Also you will get much less lag than when using LM1881/EL1883 sync cleaner (yes, no sync cleaner chip on board!).

[superg]

After the shenanigans at the other forum, are you moving the discussion here?

Yeah, it's gonna be here and I don't think I'm gonna use assemblergames for my switch support again.
It was a major pain not to be able to get a feedback and to post updates.

[Guspaz]

Bump, I will post a status update here shortly.

I sure hope it is an announcement of the new lite model. I have been excited to hear about that

gscartsw_lite has already been informally announced, I'm currently finalizing the design. I expect a final digikey package with some tuneup resistors today. Main feature in gscartsw_lite is digital sync regeneration. No matter how bad the input sync is, it's converted to digital, Altera detects it, calculates the timings and outputs it in a digital form which gets converted back to ANALOG and the level is properly set. Simply said it's supposed to fix all sync level issues. Also you will get much less lag than when using LM1881/EL1883 sync cleaner (yes, no sync cleaner chip on board!).

That's a pretty exciting development. Will it support every different sync type you might see on SCART? Like, sync-on-green, cvbs sync, luma sync, csync, etc? Right now I think the gscartsw is limited to one SoG device at a time by connecting it to input 8, and I think that works for most people (who usually just want to run a PS2 through their gscartsw), but if the new lite can handle all the different types and always output a uniform sync signal, that could solve that problem and also simplify the setup for a lot of people.

[superg]

That's a pretty exciting development. Will it support every different sync type you might see on SCART? Like, sync-on-green, cvbs sync, luma sync, csync, etc? Right now I think the gscartsw is limited to one SoG device at a time by connecting it to input 8, and I think that works for most people (who usually just want to run a PS2 through their gscartsw), but if the new lite can handle all the different types and always output a uniform sync signal, that could solve that problem and also simplify the setup for a lot of people.

All the sync signals you mention are already supported in gscartsw with an exception of SoG.
Now if we talk about Sync-on-Green (only PS2) the situation is a bit different as PS2 in VGA mode doesn't provide sync on composite SCART pin which is used by gscartsw to detect the signal. It works on input 8 as that is the default forwarded input in case nothing is detected.
I don't plan to incorporate such SoG support directly into gscartsw_lite, proper implementation of which will increase the switch price significantly (and most users don't need such support anyway). But I'm working on a board which properly separates sync from green channel to sync channel (and cleans it on green channel), the schematics is done and PCB is routed, I have to order a prototype, debug it and then it will be available to general public. The current implementation is a 2cm wide board which is installed in a middle of PS2 SCART cable (will require soldering skills). Inb4 you ask, no, it doesn't fit into SCART enclosure.

[Fudoh]

Main feature in gscartsw_lite is digital sync regeneration. No matter how bad the input sync is, it's converted to digital, Altera detects it, calculates the timings and outputs it in a digital form which gets converted back to ANALOG and the level is properly set. Simply said it's supposed to fix all sync level issues. Also you will get much less lag than when using LM1881/EL1883 sync cleaner (yes, no sync cleaner chip on board!).

definitely one of the neatest ideas I've heard in a while. Can't wait to order one.

And great to see you back here on the board.

[Guspaz]

Now if we talk about Sync-on-Green (only PS2) the situation is a bit different as PS2 in VGA mode doesn't provide sync on composite SCART pin which is used by gscartsw to detect the signal. It works on input 8 as that is the default forwarded input in case nothing is detected.

As long as the input-8 option is still available as a workaround (albeit bypassing all the new digital sync processing), I think it's definitely an acceptable solution, because there aren't that many SoG devices. And if you want to connect component video devices to the gscartsw (they obviously appear like SoG), then you can use a GARO to convert to RGBS before hitting the SCART switch.

On that note, please check compatibility of the new digital sync processing with the GARO, because it can output sync that is a little wonky in some situations. I don't know if it's a voltage issue or a grounding issue or what, but 240p NTSC Wii output through the GARO cannot sync reliably on the OSSC unless you either tweak the OSSC sync settings, or connect the GARO's VGA output to the OSSC in addition to SCART (even though you aren't using the VGA input of the OSSC, something about the attenuation or grounding seems to solve the issue).

[nakedarthur]

Great work on the switch superg, I got mine in the last batch a couple weeks ago and I've been very happy with it. I had asked on the other thread if the switch worked with a CRT_Emudriver/GroovyMAME setup, and I can now confirm it works. There is one problem I found however. Some arcade games like Mortal Kombat and R-type use very low refresh rates (53hz) and they cause the screen to roll. If I bypass the switch however they work fine. Are these signals too far out of spec for gscart to handle? Also, would it make any difference to the switch if the sync was positive or negative? Thanks!

[superg]

Great work on the switch superg, I got mine in the last batch a couple weeks ago and I've been very happy with it. I had asked on the other thread if the switch worked with a CRT_Emudriver/GroovyMAME setup, and I can now confirm it works. There is one problem I found however. Some arcade games like Mortal Kombat and R-type use very low refresh rates (53hz) and they cause the screen to roll. If I bypass the switch however they work fine. Are these signals too far out of spec for gscart to handle? Also, would it make any difference to the switch if the sync was positive or negative? Thanks!

Did you try to toggle CSYNC/OFF switch?
What do you mean by positive / negative sync? AC / DC coupling?

[nakedarthur]

Did you try to toggle CSYNC/OFF switch?
What do you mean by positive / negative sync? AC / DC coupling?

No, I have not tried with the CSYNC switch. Thanks for the tip will try that next.

The positive/negative refer to the sync pulse voltages. Negative is usually around 4-5V and drops to zero on pulse, while positive is 0-1V and rises. I believe a lot of older arcade stuff is negative sync. I saw something about it mentioned in a CRT_emudriver change-log so I figured I'd try and rule it out.

[superg]

Did you try to toggle CSYNC/OFF switch?
No, I have not tried with the CSYNC switch. Thanks for the tip will try that next.

Oh, if your image is moving vertically on the VGA connector it means that your monitor expects composite sync and switch outputs horizontal/vertical, you just have to switch VGA mode. For that you have to toggle CV/HV switch. CSYNC/OFF affects only SCART output.

[Bester]

I received my gcompsw 1.1 switch a few days ago and tested it last night (just with my gamecube ntsc-j and wii pal at this stage with a framemeister). All works perfect, cheers once again for making such an awesome product.

[avavii]

Hello everyone - I just got my gSCARTsw in Germany - it was a huge hassle with customs, but I finally prevailed. They didn't even destroy the AC adaptor due to missing CE logo in the end, which is suprising to me as I had to give them the rights to do so, before they released it.

Anyway: I would like to know: what is the best way to use the VGA Output if I want to use the framemeister -> into capture card simultaneously with using my Sony Trinitron CRT? Will a simple female VGA to SCART cable suffice? Should I connect VGA to the TV oder SCART? What's best for what?

Thanks everyone who takes the time to help me out.

[RGB0b]

Some arcade games like Mortal Kombat and R-type use very low refresh rates (53hz) and they cause the screen to roll. If I bypass the switch however they work fine. Are these signals too far out of spec for gscart to handle? Also, would it make any difference to the switch if the sync was positive or negative? Thanks!

I am having this issue as well, using a RPi (with SCART output) and custom timings to match the original arcade refresh rate. I've tried toggling everything, as well as adding an Extron device after the gscart. Connecting directly solved this issue. I'd be interested to see if anyone has a fix.

[superg]

Some arcade games like Mortal Kombat and R-type use very low refresh rates (53hz) and they cause the screen to roll. If I bypass the switch however they work fine. Are these signals too far out of spec for gscart to handle? Also, would it make any difference to the switch if the sync was positive or negative? Thanks!

I am having this issue as well, using a RPi (with SCART output) and custom timings to match the original arcade refresh rate. I've tried toggling everything, as well as adding an Extron device after the gscart. Connecting directly solved this issue. I'd be interested to see if anyone has a fix.

I have RPi 2 here, which distribution image should I use in order to have the same setup as you?
I mean with these custom timings, I can check what it outputs using oscilloscope.

[RGB0b]

I've been using RGB-Pi, as the team is trying very hard to get all games running in their original resolutions and refresh rates: http://www.rgb-pi.com/

[Darksakul]

I been now using the gscartsw Switch for little over a Month now (don't remember the exact time frame), and its been one of the best Scart switchers I ever used.

Any interference you would get would not be from this switch. If anything interference would come from the cables you use (the console system cables, most likely).


Slightly off topic, the Brandbridge switches.
I had the manual Brandbridge 5 port Switch prior to getting the gscartsw (I sold the switch off).
It isn't that awful, well it wasn't to me (image quality wise) but I ran into issues (my Sega Genesis would power on my SNES when in use) with the 5th port and had to do a small mod to fix (snipping out two diodes). I do understand Brandbridge build quality is not very consistent with some people getting almost perfect Switches and others getting complete crap.
I got one of the better Brandbridge Switches and the gscartsw is the far better switcher unit, and that ignoring the manual/Automatic differences.

If anyone still getting interference from a particular console, check your system's scart cable and it's AC adapter.
Cheaper AC Adapters are known to cause electrical noise and thus interference in the Console's video. Sometimes the Original Adapter for that console is to blame.

[nakedarthur]

Some arcade games like Mortal Kombat and R-type use very low refresh rates (53hz) and they cause the screen to roll. If I bypass the switch however they work fine. Are these signals too far out of spec for gscart to handle? Also, would it make any difference to the switch if the sync was positive or negative? Thanks!

I am having this issue as well, using a RPi (with SCART output) and custom timings to match the original arcade refresh rate. I've tried toggling everything, as well as adding an Extron device after the gscart. Connecting directly solved this issue. I'd be interested to see if anyone has a fix.

That's good to know its nothing to do with my setup then. I was just looking at the resolutions again and Mortal Kombat is definitely interesting:

resolution x: 400 pixels
resolution y: 254 pixels
video frequency: 53.20 Hz

It looks like they basically lowered the refresh down quite a bit for 14 extra lines of vertical resolution. Perhaps an amplifier or something in the gscart isn't waiting long enough to receive vertical sync pulse? Anyway, it only affects a few games I've seen so far but it was driving me crazy since I thought it might just be something with my CRT_emudriver configuration.

[superg]

That's good to know its nothing to do with my setup then. I was just looking at the resolutions again and Mortal Kombat is definitely interesting:

resolution x: 400 pixels
resolution y: 254 pixels
video frequency: 53.20 Hz

It looks like they basically lowered the refresh down quite a bit for 14 extra lines of vertical resolution. Perhaps an amplifier or something in the gscart isn't waiting long enough to receive vertical sync pulse? Anyway, it only affects a few games I've seen so far but it was driving me crazy since I thought it might just be something with my CRT_emudriver configuration.

retrorgb is going to send me his RPi with SCART output and I will check the sync and why there is a difference, now it's a good timing because I'm testing gscartsw_lite.

[Milspex]

Missed out on the last run but I will definitely pick up the gscartsw next time, it's a fantastic product

[DiegoPonga]

Hey, Superg, have you considered to create a Gscartsw with a different number of ports? Like a ×12 SCART port switch or a ×4 SCART port one and use it as an add-on.

[superg]

Hey, Superg, have you considered to create a Gscartsw with a different number of ports? Like a ×12 SCART port switch or a ×4 SCART port one and use it as an add-on.

4 port gscartsw is not going to be much cheaper as it still has to have the full circuit included. This is true for gscartsw_lite in particular as there is almost no logic per input comparing to gscartsw.
Now 12 ports is not a good number as multiplexer chips are available in 8 or 4 channels so the optimal input number would be 8.
If you need more ports you just daisy chain 2 or more switches. In practice most users are happy with 8, roughly less than 3% own more than one 8 port switch.

Also I want to mention that there is other possible switch design which allows arbitrary inputs number but significant amount of components per input. This idea was scrapped early because of quality issues it introduces (shared connection bus).

[DiegoPonga]

Hey, Superg, have you considered to create a Gscartsw with a different number of ports? Like a ×12 SCART port switch or a ×4 SCART port one and use it as an add-on.

4 port gscartsw is not going to be much cheaper as it still has to have the full circuit included. This is true for gscartsw_lite in particular as there is almost no logic per input comparing to gscartsw.
Now 12 ports is not a good number as multiplexer chips are available in 8 or 4 channels so the optimal input number would be 8.
If you need more ports you just daisy chain 2 or more switches. In practice most users are happy with 8, roughly less than 3% own more than one 8 port switch.

Also I want to mention that there is other possible switch design which allows arbitrary inputs number but significant amount of components per input. This idea was scrapped early because of quality issues it introduces (shared connection bus).

Thank you for your quick answer

I assume I'm in that minority, but I need a SCART switch with at least 12-13 ports. That's why I was asking about it

[superg]

Hey, Superg, have you considered to create a Gscartsw with a different number of ports? Like a ×12 SCART port switch or a ×4 SCART port one and use it as an add-on.

4 port gscartsw is not going to be much cheaper as it still has to have the full circuit included. This is true for gscartsw_lite in particular as there is almost no logic per input comparing to gscartsw.
Now 12 ports is not a good number as multiplexer chips are available in 8 or 4 channels so the optimal input number would be 8.
If you need more ports you just daisy chain 2 or more switches. In practice most users are happy with 8, roughly less than 3% own more than one 8 port switch.

Also I want to mention that there is other possible switch design which allows arbitrary inputs number but significant amount of components per input. This idea was scrapped early because of quality issues it introduces (shared connection bus).

Thank you for your quick answer

I assume I'm in that minority, but I need a SCART switch with at least 12-13 ports. That's why I was asking about it

Well, I myself need 3 switches so I daisy chain, still working on my perfect gaming room setup.
My standpoint is just from the sales, most people order just one, some get another one later and mostly the same people get gcompsw.

[DiegoPonga]

Well, I myself need 3 switches so I daisy chain, still working on my perfect gaming room setup.
My standpoint is just from the sales, most people order just one, some get another one later and mostly the same people get gcompsw.

Yep, I guess that's the best option. Buy one and later buy another one.

By the way, go you think costs could significatively decrease anytime soon? Probably in some couple of years?

[superg]

By the way, go you think costs could significatively decrease anytime soon? Probably in some couple of years?

Not sure on that, lite price is $180 with power supply included, that's the lowest I can do at the moment.
It all depends on factors like component pricing, manufacturing costs and case laser cutting and from my experience those costs usually don't go lower.
Lite is optimal on price / features, much better than gscartsw in that regard.

[DiegoPonga]

Not sure on that, lite price is $180 with power supply included, that's the lowest I can do at the moment.
It all depends on factors like component pricing, manufacturing costs and case laser cutting and from my experience those costs usually don't go lower.
Lite is optimal on price / features, much better than gscartsw in that regard.

Thank you once again!

Then I'll probably ask for at least one of those Gscartsw Lite by the end of the year. And probably another one in some couple of years.

By the way, have you tested your switch(es) with YPbPr-through-SCART? I mean, instead of a SCART with composite or RGB signal, a SCART with a YPbPr signal. Allegedly, pins 11, 7 and 15 can carry Y, Pb and Pr signals, respectively.

That wouldn't have any issues in switches like yours, would that?

[Guspaz]

It's electrically identical to RGsB (sync on green). So his same answer applies: you'll need to use input 8 and it won't benefit from the digital sync regeneration.

[superg]

By the way, have you tested your switch(es) with YPbPr-through-SCART? I mean, instead of a SCART with composite or RGB signal, a SCART with a YPbPr signal. Allegedly, pins 11, 7 and 15 can carry Y, Pb and Pr signals, respectively.

That wouldn't have any issues in switches like yours, would that?

It will work, Y carries sync and it will be detected just fine. But obviously it's not going to convert it to RGBS.

[Wolf_]

By the way, have you tested your switch(es) with YPbPr-through-SCART? I mean, instead of a SCART with composite or RGB signal, a SCART with a YPbPr signal. Allegedly, pins 11, 7 and 15 can carry Y, Pb and Pr signals, respectively.

That wouldn't have any issues in switches like yours, would that?

It will work, Y carries sync and it will be detected just fine. But obviously it's not going to convert it to RGBS.

Running it through the gscart is great for two reasons:
1) It is a scart switch so it keeps things simple and easy to use.
2) The gscart has a built in sync stripper which you need if you want to connect it to the extron for RGsB.

The only simpler way to get RGsB out of a ps2 would be to connect it directly to an ossc and if you have multiple consoles you will probably want to just connect the gscart to the ossc anyways.

tl;dr gscart is good.

[DiegoPonga]

By the way, have you tested your switch(es) with YPbPr-through-SCART? I mean, instead of a SCART with composite or RGB signal, a SCART with a YPbPr signal. Allegedly, pins 11, 7 and 15 can carry Y, Pb and Pr signals, respectively.

That wouldn't have any issues in switches like yours, would that?

It will work, Y carries sync and it will be detected just fine. But obviously it's not going to convert it to RGBS.

So, I don't need anything weird in order to build my own YPbPr-through-SCART adaptor.

Simply this:
Pins 2 and 6 for audio as well as pin 4 for ground
Pins 5, 9 and 12 for YPbPr ground
Pins 7, 11 and 15 for YPbPr

And that's all. No use of anything else. Pins 20 and 8 unplugged. And there won't be any problem if I plug two of these into Gscart, would they? I don't need input 8 for this and I can keep it for PS2's SoG, can't I?

Thanks a lot, by the way!!