GScartsw Dip Set

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Rock Man
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GScartsw Dip Set

Post by Rock Man »

DIP 1: Enable sync regeneration

I was curious about the sync regeneration here. Upon diving into My Life In Gaming's review: https://www.youtube.com/watch?v=998tBzpJhVo

This replaces sync stripping. Can anyone confirm whether this will give you at least marginally better results than using a stripper?

DIP 2: Disable sync on green compensation

Is this used to mod the video in PS2's? This one looks familiar to me. I suspect it allows certain displays to detect PS2 in component?

DIP 3: Enable Sega Master System correction

Wasn't aware the Master System needed correcting. :shock: What does this function aim to do with Sega's scrappy 8-bit machine?

Finally, I have a MiSTer FPGA cable from Retro Access. I think it outs composite sync, it didn't work with my previous switchers, I suspect that it scuffed at the the male SCART2BNC I was using due to it having a built-in sync stripper. I'm aware that sync strippers and composite sync are unnecessary to use together.

Let's say I turn off sync regeneration, would doing this allow me to use my CSYNC cable on the MiSTer? If not then I'll buy one without CSYNC later on.

Last thing, those dip buttons are tiny. What might I use to switch them up and down? Tip of a pen?
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Kez
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Re: GScartsw Dip Set

Post by Kez »

I'll try to answer what I can:
1: Sync regeneration I think detects the current sync and then generates a digital equivalent, which results in clean sync like a sync stripper but through a different method. If you're having issues you think might be sync related, or if you need clean csync for some reason then it should do the job. I have no idea if mine is on or off to be honest. I have definitely messed around with that switch when debugging other issues.

2: So the gscartsw detects sync on green, and routes the sync to the sync output pin. This is always on I believe, but the DIP switch makes it also remove the sync from the green channel as it can mess up the colours on some displays. Should be okay to leave it on, although if you're rooting YPbPr through the switch it may break that if left on? Normally the only time RGsB (sync on green) comes up is the PS2, which switches to RGsB when outputting 480p over SCART.

3: I think this is for if you get like a weird skew or flagging on certain PVMs or BVMs. Probably okay to leave this off, and you'll know if you need it. :mrgreen:


It may be that your MiSTer cable is missing switching voltage on the SCART pins. Most switches work by detecting voltage on pin 8, which is the device saying it is on and sending out a signal. This is the correct SCART spec but a lot of hobby cables/devices don't have it as the switching voltage isn't needed for video and things like scalers, scart to BNC adapters etc don't use it. The gscartsw detects activity on the sync pin rather than looking for this switching voltage, so the cable may just work.

I just use a pair of tweezers or a small screwdriver to flip the switches. Whatever I have to hand really.
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Gara
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Re: GScartsw Dip Set

Post by Gara »

1. Sync regeneration has been quite handy in my own setup and has performed better than a sync stripper built into a cable when I've had sync issues. I just keep it on and forget about it. If your outputting cable has a sync stripper I'd switch over to one without. You shouldn't double up on sync strippers.

2. I forgot what position of the sync on green switch is the desired one. I think enabling that switch is what's needed to run YPbPr into the switch with an adapter.

3. Superg made a lot of effort to try and fix sync issues on Master System and PC Engine when using certain professional CRT monitors. He ended up only being able to fix Master System. You can see an example in the video linked below in the oscilloscope section.

Did you order a custom MiSTer cable from Retro Access? The default one should work without issue. That's what I use and I keep sync regeneration enabled. I don't use a sync stripper on the output though.


The dipswitches are not terribly hard to use and you'll likely not need to be revisiting them often. Use anything small and pointy. Toothpick, paperclip, small screwdriver, etc.



Bob talks about some of these things in this video. The Oscilloscope section goes over the jumpers.
https://www.youtube.com/watch?v=KeMPPyJAM_w

Cool optional case for the Gscartsw. Completely optional and a pain in the butt to install, but it makes it look nice.
https://www.laserbear.net/products/gsca ... mper-cases
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Rock Man
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Re: GScartsw Dip Set

Post by Rock Man »

Thanks guys, both of you have been helpful.

I'll be performing a few tests, one being checking the switch position of that sync regen. Something tells me that it's up because my games looked the same way they would when connected to the Otaku/Shinybow switch using a SCART2BNC with the stripper in cable.

Right now my PS2 is connected via SCART. Haven't tested it yet so testing that will be another priority. I ordered a component2scart switch cable, looking forward to testing but first am waiting for RA to ready my order.

After PS2 gonna take a look at the Master System. Thanks for the video!

The only thing I said about the MiSTer cable is to make sure it has CSYNC, Euro SCART with NTSC, and works on a PVM. The end result was it gigaphailed to work with my equipment. Totally my fault for asking for CSYNC I should have specifically requested sync over composite video then I wouldn't have had this problem. Either way both of you said the MiSTer should work now that I've introduced the gscartsw into the mix. Now I have to actually move it back over to the retro game room (was set-up on an HDTV), and if it works I have a metric fuck ton of update all script that needs to be, well updated. Part of the fun. :lol:

EDIT: Is it possible to flip the dip switches while you have a console turned on, it won't damage anything will it?

Noticed something about my TV thats been bugging me. When I plug in my BNC cables on the INPUT side of the PVM I get a dimmed picture! Tried sync regeneration on this input and it didn't do anything. But when BNC is plugged to output the picture is amazing! Bright colors and all!

Couldn't find a difference in sync regeneration on the output side either

Forgot to.mention, BUYING A CASE! :D
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Kez
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Re: GScartsw Dip Set

Post by Kez »

I flip the DIP switches when the console is running to see what happens and haven't had any issues - it never occurred to me that I shouldn't.. :mrgreen: But I am not going to totally endorse it as I don't know for sure!

The dimmed video is normal behaviour. Video signals are supposed to have 75ohm termination to be completely in spec. Professional monitors are designed to be daisy chained, and the termination only happens at the end of course, so once you're at the end of the daisy chain you're supposed to put 75 ohm termination on the unused output, (like this). However, some monitors have little mechanisms on the output connectors which automatically terminate correctly when there is nothing attached to them - sounds like this is what your monitor is doing.

Because it's higher impedance, the terminated video is dimmer but technically this is the correct signal. However, if your tube is a bit faded from use or maybe you're in a bright room the maximum brightness achieved might not be enough for you. In that case you could use the output connectors like you are doing. It shouldn't cause any issues (possibly some ghosting if you're running really long cables I think), but I would still prefer to have max brightness on a terminated input vs. using unterminated and not maxing the brightness.
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Rock Man
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Re: GScartsw Dip Set

Post by Rock Man »

Kez wrote:I flip the DIP switches when the console is running to see what happens and haven't had any issues - it never occurred to me that I shouldn't.. :mrgreen: But I am not going to totally endorse it as I don't know for sure!

The dimmed video is normal behaviour. Video signals are supposed to have 75ohm termination to be completely in spec. Professional monitors are designed to be daisy chained, and the termination only happens at the end of course, so once you're at the end of the daisy chain you're supposed to put 75 ohm termination on the unused output, (like this). However, some monitors have little mechanisms on the output connectors which automatically terminate correctly when there is nothing attached to them - sounds like this is what your monitor is doing.

Because it's higher impedance, the terminated video is dimmer but technically this is the correct signal. However, if your tube is a bit faded from use or maybe you're in a bright room the maximum brightness achieved might not be enough for you. In that case you could use the output connectors like you are doing. It shouldn't cause any issues (possibly some ghosting if you're running really long cables I think), but I would still prefer to have max brightness on a terminated input vs. using unterminated and not maxing the brightness.
I see so it's a Scart termination thing. I have a Scart cable for Genny when I plug it in on my XRGB series through the HDTV the brightness is so high it makes the game unplayable. That's because the 75ohms wasn't in there so after seeing that I see what's going on here. The output on my PVM is giving me the proper termination so I get controlled brightness.

The Genesis thing isn't a big deal as I have plenty of cables for it. I'm just acknowledging the the importance of 75 ohms

The MiSTer is a bust! Jumping picture, it does that when the thing is set to progressive--!!! Just had an epiphany!! I'm going to look up how to set my MiSTer to 480i real quick, need to mess with some INI settings! It should work since both of you confirmed it does

I'll hit that and get back. Other than MiSTer all is working as it should

EDIT: Nm MiSTer now works! After some tweaks to the ini file :oops:

EDIT 2: Getting scratchy sound, mostly on stereo. When I remove the gscart and connect these consoles raw it goes away! I wish to play my sources through the gscart, wondering if there is a fix to this.
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