BVM-A20F1M Sega consoles Sync problems

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PeterWar
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Re: BVM-A20F1M Sega consoles Sync problems

Post by PeterWar »

All I can say is that I own a gscartsw_lite and I think it's an amazing piece of equipment, I noticed no image degradation at all.

If superg makes an upgrated version capable to solve BVM-A sync issues I would buy one for sure.
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asasra
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Re: BVM-A20F1M Sega consoles Sync problems

Post by asasra »

hello

has anyone been able to establish if the gscartsw is able to fix the sync issues with AES and SMS on an a-series BVM?

or even by means of some other device.

thanks
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superg
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Re: BVM-A20F1M Sega consoles Sync problems

Post by superg »

asasra wrote:hello

has anyone been able to establish if the gscartsw is able to fix the sync issues with AES and SMS on an a-series BVM?

or even by means of some other device.

thanks
SMS issue was fixed but nothing else.
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asasra
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Re: BVM-A20F1M Sega consoles Sync problems

Post by asasra »

thank you!
PeterWar
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Re: BVM-A20F1M Sega consoles Sync problems

Post by PeterWar »

I'll be buying an NTSC Megadrive and Dreamcast shortly.
I would very much appreciate if you could please share the serial ID and (ideally board revision) of the megadrive and dreamcast that have been tested to work on the BVM-A20F1M.
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asasra
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Re: BVM-A20F1M Sega consoles Sync problems

Post by asasra »

I would like to help, unfortunately my stuff is in storage in a different city :/
PeterWar
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Re: BVM-A20F1M Sega consoles Sync problems

Post by PeterWar »

I've made some progress here.

Consoles currently working on my BVM-A20F1M:

NES NTSC60Hz RGB Modded: Fully working with modders supplied cable.
SNES PAL 50/60Hz modded: Working with RGB using retrogaming cable sync on luma.
N64 PAL RGB Modded: Fully working, waiting for a moded N64 with deblur filer.
Neo-Geo AES: Working with composite, picture is skewed with RGB. An improvement could be to buy a S-Video cable (if anyone know where to find one please let me know).

New additions:
Sega Saturn Mk1 PAL 50Hz (Made in Indonesia S/N AD51022662): Working with RGB with the boxed cable.
Sega Dreamcast NTSC (S/N 058000042397): Working with composite and RGB with boxed cables. Allso fully working in 31KHz/480p!!! (using Sega Dreamcast PACKAPUNCH RGB 480p SCART cable from retrogaming cables). The dreamcast is AMAZING in 480p with the BVM-A20F1M. Interestingly when I toggle the 15KHz/576i switch it goes out of sync. Sync regeneration on my gscartgw does not help. It is really not much of an issue as most games including all the games I wanted to play support VGA mode (converted to 31Khz/480p throught this cable).

Consoles not working yet:
PAL Megadrive/PAL 32x: Out of sync with composite and RGB. Will try S-Video once S-video adapter for Sega Genesis/Mega Drive Model 1 in Taobao is back on stock. Another solution for RGB could be to buy a NTSC-J console.

Master System 2: Out of sync, a possible solution could be to buy a newer gscartsw version.
PeterWar
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Re: BVM-A20F1M Sega consoles Sync problems

Post by PeterWar »

Update: Not sure if rellevant to the discussion but my Everdrive 64 works correctly on my French RGB moded PAL N64 with N64 PAL games but all NTSC region games go out of sync with the BVM-A20F1M.

S2SDNES on my switchless 50/60HZ SNES plays all games from all regions just fine.

EDIT: Yes it is relevant. Everdrive N64 NTSC games work just fine on my Sony Triniton TV.
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asasra
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Re: BVM-A20F1M Sega consoles Sync problems

Post by asasra »

sorry nothing to add here, just wanted to say I'm interested in whatever comes out of this
all my shit is in storage and has to stay there for the foreseeable future :/
PeterWar
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Re: BVM-A20F1M Sega consoles Sync problems

Post by PeterWar »

Ok I've made some progress:

1- I can confirm that my japanese Playstation 1 syncs perfectly with the BVM-A20F1M and BKM-68x.

2- I’m very glad to report that the MicroConverter HDMI to SDI works on the BVM-A20F1M with BKM-62HS board running in HDSDI 444 YPBPR mode and my Nintendo Switch setup in 720p mode :) I have one SDI outcable connected to port 1 in of the BKM-62HS.

Image

So this raises the possibility of using OSCC or MicroTik to upscale 240p to 720p and run with full color palete. It is my belief (but could be wrong) that this setup would get us no input lag (I think this setup would add only 1 or two scanlines of lag, not frames).

Now all what’s left to do I believe is figure out how to make my OSCC output 720p so that it is accepteable for the BKM-62HS, Adam from OSCC is already looking into it.
Saturngamer81
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Re: BVM-A20F1M Sega consoles Sync problems

Post by Saturngamer81 »

Might aswell jump into this thread being an owner of 2x a20f's and a brand new A24e1wm a d24 etc. I own only 1 68x BTW (its in the A24 :) . My take on the A series is that i prefer them even with the sync issues with certain consoles compared to the D series. Heres why: When using resolution 480p and above via RGB the 68x performs better than the d24. Its easier to get it to sync and achieve a stable image in 720p 1080i etc. In fact the 68x can be fooled with related timing resolutions such as 1440i from a pc, looks great. If you want you can even pump into it 540p etc.

As far as hdsdi goes using a gefen pro scaler you can get real 444 video from whatever source you desire and i beleive it handles it much better than the noisy 422 D series.

THE THORN IN MY SIDE: Neo geo MVS

I own several mvs boards and have acollection of carts plus the NEO SD MVS.. unfortunatley I havent been able to sync it with the 68x. I have tried replacing the crystal, using an extron with no luck.

Things to try: -Maybe converting the signal to composite and tapping that as a sync signal might do the trick.
- upscale to 480p since the 68x might be more accepting at higher resolutions.

I could always throw in the towel and get a AES which has the scew and tapp the sync into an extron, however that would be expensive.
Anyways whatever the issues the A series are an amazing monitor and in my opinion the most versatile for watching movies, retro gaming and ofc 1440i pc gaming heaven.
fernan1234
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Re: BVM-A20F1M Sega consoles Sync problems

Post by fernan1234 »

Saturngamer81 wrote:When using resolution 480p and above via RGB the 68x performs better than the d24.
Are you comparing this the D series via RGB as well, and not through SDI/HD-SDI on the D series? Because in my experience you can feed all of these resolutions via RGB to a D24, D20, etc. without issues. I didn't try 1440i though, did that one fail to sync on the D24 via RGB?
Saturngamer81
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Re: BVM-A20F1M Sega consoles Sync problems

Post by Saturngamer81 »

fernan1234 wrote:
Saturngamer81 wrote:When using resolution 480p and above via RGB the 68x performs better than the d24.
Are you comparing this the D series via RGB as well, and not through SDI/HD-SDI on the D series? Because in my experience you can feed all of these resolutions via RGB to a D24, D20, etc. without issues. I didn't try 1440i though, did that one fail to sync on the D24 via RGB?
So yes technically you are correct the d24 can be fed these resolutions via rgb, however its more fussyer as i had issues getting a stable image from my pc at 1080i or 720p though it is possible,, the a24 was more forgiving, all it needed was a custom resolution with negative sync and then a T connector for the h and v sync lines. I could be wrong but having had both to compare the a24 via the 68x has been easier to work with for hd resolutions.. even my dreamcast worked better via vga 480p on my a24 than the d24: which had scewing at the top of the image.

But hey some of our experiences can differ depending on equipment combination etc therefore giving a different outcome and opinion. as regards to hdsdi im pretty certain the a24 performs better including its ability to produce a 444 image. both are great monitors though cant beat the d24 for 240p gaming, but the a24 to me is a better monitor by a slight fraction for what it is.
fernan1234
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Re: BVM-A20F1M Sega consoles Sync problems

Post by fernan1234 »

Saturngamer81 wrote:So yes technically you are correct the d24 can be fed these resolutions via rgb, however its more fussyer as i had issues getting a stable image from my pc at 1080i or 720p though it is possible,, the a24 was more forgiving, all it needed was a custom resolution with negative sync and then a T connector for the h and v sync lines. I could be wrong but having had both to compare the a24 via the 68x has been easier to work with for hd resolutions.. even my dreamcast worked better via vga 480p on my a24 than the d24: which had scewing at the top of the image.
Yes our experience will vary based on equipment. I don't think using a simple T connector for HV sync is ideal, and that may be the source of the issues you experienced. I use an Extron RGB interface to combine the sync from converting HDMI to VGA/RGBHV, and that may be why I never need to do any configuration to feed any ED and HD resolutions via RGB from PC (Windows as well as MacOS) or something like a MiSTer or Raspberry Pi, as well as sources processed by an Extron scaler. It all just works. Skews at the top can be fixed easily by turning VCR mode on (or the SERR dipswitch on an Extron box).

I can see HD-SDI being an issue or inferior, but then I think that should never be used in the first place since there are perfect DAC solutions via RGB.
Saturngamer81
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Re: BVM-A20F1M Sega consoles Sync problems

Post by Saturngamer81 »

fernan1234 wrote:
Saturngamer81 wrote:So yes technically you are correct the d24 can be fed these resolutions via rgb, however its more fussyer as i had issues getting a stable image from my pc at 1080i or 720p though it is possible,, the a24 was more forgiving, all it needed was a custom resolution with negative sync and then a T connector for the h and v sync lines. I could be wrong but having had both to compare the a24 via the 68x has been easier to work with for hd resolutions.. even my dreamcast worked better via vga 480p on my a24 than the d24: which had scewing at the top of the image.
Yes our experience will vary based on equipment. I don't think using a simple T connector for HV sync is ideal, and that may be the source of the issues you experienced. I use an Extron RGB interface to combine the sync from converting HDMI to VGA/RGBHV, and that may be why I never need to do any configuration to feed any ED and HD resolutions via RGB from PC (Windows as well as MacOS) or something like a MiSTer or Raspberry Pi, as well as sources processed by an Extron scaler. It all just works. Skews at the top can be fixed easily by turning VCR mode on (or the SERR dipswitch on an Extron box).

I can see HD-SDI being an issue or inferior, but then I think that should never be used in the first place since there are perfect DAC solutions via RGB.

The issues i experienced was with various attempts via an extron and the t connector. I am aware of the vcr option on the d24. Since you have written your experience I wonder if the D24 had any slight revisions which may explain differing outcomes between people. Ive heard through the grape vine that early d24s didnt even support 720p but i digress.

HD sdi i use allot for video content, actually i use my a24 mostly for watching films etc as it is calibrated. one thing i noticed however is that when i used my pc via hdsdi i didnt see any latency compared to my modern lcd monitor outputting the same content. meaning the latency on my converter was more or less the same as my lcds latency. useless information XD.

I would like to see if you succeed with 1440i on the d24. your setup sounds like it should allow it without no issues if the d24 will bite.
fernan1234
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Re: BVM-A20F1M Sega consoles Sync problems

Post by fernan1234 »

720p definitely works. Don't see why it shouldn't on any "multiformat" monitor.

I don't know how to get 1440i out of any of my sources, but I may give it a try at some point. Part of my success may be that I've mainly used standard CEA resolutions (true 480p, 720p and 1080i, as opposed to something personally customized on the end of a PC graphics card), though I also didn't have issues with DTV or PC resolutions like 640x480, etc.).
jwrose
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Re: BVM-A20F1M Sega consoles Sync problems

Post by jwrose »

Been getting caught up on this thread. I've been putting together my setup in the last year and wish I had found this before. Anyway, I've dealt with the issue (called flagging) where the top of the image is pulled to the side. Just to provide my experience:

I have 14 sysstems hooked up and I have 3 with signal issues. AES and T16 are clearly flagging, not sure about SMS:

I was able to solve the AES & T16 issue using an Extron RGB 203. Any Extron RGB with the SERR switch SHOULD fix it. I like the 203 because it has an LCD screen to confirm its getting a signal. I have a Extron Crosspoint in my setup and I had to use the Extron RGB AFTER the signal passed through the Crosspoint. I have no idea why, but it just wouldn't fix the issue if I sent it through the Crosspoint after the Extron RGB. Another benefit of a Crosspoint is you can, essentially, thread the signals in and out to use the Extron RGB or not. Meaning, I can send all my SCART device into input 1 and then all are sent to my BVM through output 1. BUT, for the Turbo and the AES, I can send the signal from input 1 to output 3, which sends it to the Extron RGB. Then, I can go from Input 8 (which is the Extron RGB In) and then back out Output 1 (using the same cable as before) with the cleaned up signal. Everything uses the same cables and then is just routed to appropriate devices. I do a similar thing with a RGB2COMP to send my 240p/480i systems to a consumer TV. The RGB systems can be routed through an additional output/input to process it through RGB2COMP, and the composite devices can just go directly to the TV.

@PeterWar, I saw you mentioned the flagging issue on the Neo Geo. The solution I used above *SHOULD* fix it.

So, currently, it sounds like the only solution for the SMS is a newer gscartsw? I was hoping for a cheaper solution since my setup is nearly complete :\ I wonder if there are any other Extron devices that could fix it? Does anyone know, from a technical level, what the issue is? I read somewhere it had to do with "horizontal slices" or something like that.
skum
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Re: BVM-A20F1M Sega consoles Sync problems

Post by skum »

jwrose wrote:Does anyone know, from a technical level, what the issue is? I read somewhere it had to do with "horizontal slices" or something like that.
I've been looking briefly into this, so as far as I can understand (and anyone please correct me if I am wrong) this happens:
Some consoles when in the vertical sync interval do not have the horizontal sync pulses. As they are missing, the PLL circuit of the monitor loses sync and has to reacquire lock. Thus, as I see it, the solution must be to re-generate the sync signal by locking on, detect vsync, and *keep* generating hsync pulses during vsync.
daty2k1
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Re: BVM-A20F1M Sega consoles Sync problems

Post by daty2k1 »

@jwrose Do you have a PS1 in your systems? Any issue when playing import games?

Also, I searched but could not find a definitive answer: do Extron devices introduce any form of lag? From my understanding, it shouldn't seeing there is no framebuffer of any sort but you never know.
jwrose
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Re: BVM-A20F1M Sega consoles Sync problems

Post by jwrose »

daty2k1 wrote:@jwrose Do you have a PS1 in your systems? Any issue when playing import games?

Also, I searched but could not find a definitive answer: do Extron devices introduce any form of lag? From my understanding, it shouldn't seeing there is no framebuffer of any sort but you never know.
Interesting question about import PS1 games. Right now my PS1 or PS2 are region locked. I'm hoping to get that modded later this year. Is that a common issue?

Extron Crosspoints do not, it just passes the signal. I've never noticed any lag for the Extron RGB. I just fired up the 240p test suite on my T16 and went to the controller test and pressed buttons and watch them light up and it felt pretty instantaneous. I then sent the signal to the BVM bypassing the Extron RGB and it seemed to be identical.
jwrose
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Re: BVM-A20F1M Sega consoles Sync problems

Post by jwrose »

skum wrote:
jwrose wrote:Does anyone know, from a technical level, what the issue is? I read somewhere it had to do with "horizontal slices" or something like that.
I've been looking briefly into this, so as far as I can understand (and anyone please correct me if I am wrong) this happens:
Some consoles when in the vertical sync interval do not have the horizontal sync pulses. As they are missing, the PLL circuit of the monitor loses sync and has to reacquire lock. Thus, as I see it, the solution must be to re-generate the sync signal by locking on, detect vsync, and *keep* generating hsync pulses during vsync.
that seems to make sense. At least it sounds a lot better than whatever "horizontal slices" I remember reading somewhere. :lol:

I do know someone who's more knowledgable than I am about that, I'll see if he has any thoughts- I think that description makes more sense than what I passed along to him. If anyone else has more information, I'd love to hear it!

Worst case scenario, I'm "stuck" playing my SMS on my consumer set (it still looks great going through a RGB2COMP) but its the only system I can't get on the BVM. I would like to solve that issue for under $100! :mrgreen:
daty2k1
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Re: BVM-A20F1M Sega consoles Sync problems

Post by daty2k1 »

Yes there is a known issue about PS1 where playing a PAL game on an NTSC system or vice-versa will result in non standard display frequencies (and games running about 1% slower / faster compared to playing on the correct system). 99% of the time it is not a problem as most consumer CRTs will accept it but on this particular BVM, it doesn't work and you get a "rolling" picture. Some info here: https://nfggames.com/forum2/index.php?topic=5744.0

Good to know about the lag, thanks.
jwrose
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Re: BVM-A20F1M Sega consoles Sync problems

Post by jwrose »

daty2k1 wrote:Yes there is a known issue about PS1 where playing a PAL game on an NTSC system or vice-versa will result in non standard display frequencies (and games running about 1% slower / faster compared to playing on the correct system). 99% of the time it is not a problem as most consumer CRTs will accept it but on this particular BVM, it doesn't work and you get a "rolling" picture. Some info here: https://nfggames.com/forum2/index.php?topic=5744.0
Ah, interesting- good to know. That is REALLY weird as the BVM is supposed to play nice with PAL. When you first said "import" I was thinking Japanese games (which would be even stranger, of course). I didn't have any plans for PS1 PAL games, but I'll have to remember that if one ever does grab my attention. :\
daty2k1
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Re: BVM-A20F1M Sega consoles Sync problems

Post by daty2k1 »

Yeah of course if you have an NTSC system it shouldn't be a problem. It is mostly an issue if you are in my case and you want to play NTSC games on a PAL system. I will probably try to get an US PS1 in the end as it is the only system where I have issues.
skum
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Re: BVM-A20F1M Sega consoles Sync problems

Post by skum »

daty2k1 wrote:Yeah of course if you have an NTSC system it shouldn't be a problem. It is mostly an issue if you are in my case and you want to play NTSC games on a PAL system. I will probably try to get an US PS1 in the end as it is the only system where I have issues.
You can use the DFO to fix this, restore composite color also.
jwrose
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Re: BVM-A20F1M Sega consoles Sync problems

Post by jwrose »

Doing some googling I found a very technical description of the SMS issue here, just from last year: https://www.hdretrovision.com/blog/2019 ... ling-short
I did find this point at the bottom intersting:
5.) Fixing CSYNC errors after generation is very costly, unreliable, and non-universal. It’s also very difficult to do for interlaced systems.

He does mention the TG16 as well in this. So, in short, the TG16, Neo Geo AES, and Master System all have different CSYNC issues. The "SERR" (serration pulse selection), does the trick for the AES and TG16- which must have similar issues. To his point, CSYNC fixes are not universal :(

Nothing new in that statement to us, but nice to see it explained/supported by someone who knows far more that I do. Im going to look into it a bit more..

He mentions a part 3, which hasn't been published yet :\

Just some somewhat related information. I tried to use a RGB2COMP to see if converting the signal to component would resolve the SMS issue, but it didn't.
Ikaruga11
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Re: BVM-A20F1M Sega consoles Sync problems

Post by Ikaruga11 »

The problem isn't the A-Series BVM. The problem is the consoles. Their sync is out of spec and needs to be corrected.
jwrose
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Re: BVM-A20F1M Sega consoles Sync problems

Post by jwrose »

GeneraLight wrote:The problem isn't the A-Series BVM. The problem is the consoles. Their sync is out of spec and needs to be corrected.
Yep. SERR feature on Extron RGB devices can fix the signal for Neo Geo AES and TG16, but Master System signals seems to be fixable with a gscartsw.

I personally have experience solving the first two with an Extron RGB 203 but hoping there's another way to fix the SMS signal (cheaper than a gscartsw).
jwrose
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Re: BVM-A20F1M Sega consoles Sync problems

Post by jwrose »

Anyone have an experience with sync strippers? I wonder if that could help with the SMS on a BVM A or D series. Thoughts or am I totally misunderstanding sync strippers?
skum
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Re: BVM-A20F1M Sega consoles Sync problems

Post by skum »

jwrose wrote:Anyone have an experience with sync strippers? I wonder if that could help with the SMS on a BVM A or D series. Thoughts or am I totally misunderstanding sync strippers?
You're misunderstanding sync strippers, at least in this context. The sync stripper won't recreate the missing signals, it will just separate sync information from a given signal.
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