shmups.system11.org

Shmups Forum
 
* FAQ    * Search
 * Register  * Login 
It is currently Fri Sep 20, 2019 6:55 pm View unanswered posts
View active topics



Post new topic Reply to topic  [ 100 posts ]  Go to page 1, 2, 3, 4  Next
Author Message
 Post subject: Retro-Access Releases Dreamcast 15Khz/31Khz Scart/BNC Cables
PostPosted: Thu May 02, 2019 6:13 pm 


User avatar

Joined: 01 Dec 2006
Posts: 2043
Scart: https://retro-access.com/products/dream ... cart-cable

BNC: https://retro-access.com/products/dream ... -bnc-cable

Does anyone know if these fixes out-of-the-box the overblown video and RGB levels?


Top
 Offline Profile  
 
 Post subject: Re: Retro-Access Releases Dreamcast 15Khz/31Khz Scart/BNC Ca
PostPosted: Thu May 02, 2019 6:18 pm 


User avatar

Joined: 06 Mar 2006
Posts: 11836
Location: Germany
And for those in Europe Retrogamingcables UK opened preorders for his version of the Scart cable today as well.

https://www.retrogamingcables.co.uk/seg ... -480P-MODE


Last edited by Fudoh on Thu May 02, 2019 6:52 pm, edited 1 time in total.

Top
 Offline Profile  
 
 Post subject: Re: Retro-Access Releases Dreamcast 15Khz/31Khz Scart/BNC Ca
PostPosted: Thu May 02, 2019 6:20 pm 


User avatar

Joined: 01 Dec 2006
Posts: 2043
Fudoh wrote:
And for those in Europe Retrogamingcables UK opened preorders for his version of the Scart cable today well.

https://www.retrogamingcables.co.uk/seg ... -480P-MODE


Thanks for pointing it out, did RGC confirm whether or not it attenuates video levels and rgb levels?


Top
 Offline Profile  
 
 Post subject: Re: Retro-Access Releases Dreamcast 15Khz/31Khz Scart/BNC Ca
PostPosted: Thu May 02, 2019 6:46 pm 



Joined: 21 Aug 2016
Posts: 514
Citrus was involved with the Retro Access one, anyway, so while I can't confirm or deny how the levels look, he seems like he knows what he's doing.


Top
 Offline Profile  
 
 Post subject: Re: Retro-Access Releases Dreamcast 15Khz/31Khz Scart/BNC Ca
PostPosted: Thu May 02, 2019 7:05 pm 


User avatar

Joined: 01 Dec 2006
Posts: 2043
thebigcheese wrote:
Citrus was involved with the Retro Access one, anyway, so while I can't confirm or deny how the levels look, he seems like he knows what he's doing.


Great news, Drew just confirmed to me that their Dreamcast cables are indeed attenuated!


Top
 Offline Profile  
 
 Post subject: Re: Retro-Access Releases Dreamcast 15Khz/31Khz Scart/BNC Ca
PostPosted: Fri May 03, 2019 12:57 pm 


User avatar

Joined: 25 Dec 2013
Posts: 608
Location: Indiana
Yes, RGB max levels are right at 700mv.

The CSYNC also has the serration pulses so it works on the BVM D & A series monitors that lack the vcr button in 480p mode.


Top
 Offline Profile  
 
 Post subject: Re: Retro-Access Releases Dreamcast 15Khz/31Khz Scart/BNC Ca
PostPosted: Fri May 03, 2019 2:24 pm 


User avatar

Joined: 20 Jul 2017
Posts: 457
citrus3000psi wrote:
The CSYNC also has the serration pulses so it works on the BVM D & A series monitors that lack the vcr button in 480p mode.


Wow, that's awesome! So anyone who has an annoying curve at the top of your picture when using DC in 480p - this will eliminate it.


Top
 Offline Profile  
 
 Post subject: Re: Retro-Access Releases Dreamcast 15Khz/31Khz Scart/BNC Ca
PostPosted: Fri May 03, 2019 4:28 pm 


User avatar

Joined: 09 Apr 2014
Posts: 238
Location: UK
Lawfer wrote:
Fudoh wrote:
And for those in Europe Retrogamingcables UK opened preorders for his version of the Scart cable today well.

https://www.retrogamingcables.co.uk/seg ... -480P-MODE


Thanks for pointing it out, did RGC confirm whether or not it attenuates video levels and rgb levels?


I asked RGC about high RGB levels and detail clipping and got a short reply saying:

Quote:
we have resistors and caps on the RGBS lines


Top
 Offline Profile  
 
 Post subject: Re: Retro-Access Releases Dreamcast 15Khz/31Khz Scart/BNC Ca
PostPosted: Sat May 04, 2019 1:07 pm 


User avatar

Joined: 05 Mar 2018
Posts: 882
citrus3000psi wrote:
Yes, RGB max levels are right at 700mv.

The CSYNC also has the serration pulses so it works on the BVM D & A series monitors that lack the vcr button in 480p mode.


Gunstar wrote:
Lawfer wrote:
Fudoh wrote:
And for those in Europe Retrogamingcables UK opened preorders for his version of the Scart cable today well.

https://www.retrogamingcables.co.uk/seg ... -480P-MODE


Thanks for pointing it out, did RGC confirm whether or not it attenuates video levels and rgb levels?


I asked RGC about high RGB levels and detail clipping and got a short reply saying:

Quote:
we have resistors and caps on the RGBS lines


are there full attenuator networks to keep impedance matched? or just series resistors?


Top
 Offline Profile  
 
 Post subject: Re: Retro-Access Releases Dreamcast 15Khz/31Khz Scart/BNC Ca
PostPosted: Sun May 05, 2019 3:12 pm 


User avatar

Joined: 09 Apr 2014
Posts: 238
Location: UK
maxtherabbit wrote:
are there full attenuator networks to keep impedance matched? or just series resistors?


That's a great question and I've passed it on to RGC, I'll reply back if I hear anything.


Top
 Offline Profile  
 
 Post subject: Re: Retro-Access Releases Dreamcast 15Khz/31Khz Scart/BNC Ca
PostPosted: Sun May 05, 2019 4:45 pm 


User avatar

Joined: 06 Feb 2005
Posts: 799
Location: Italy
Does RGC employ impedance-matched cables and connectors to begin with? I thought that was the main difference between RGC and RCA cables. (Whether that's worth the extra cost though, I don't really know)


Top
 Offline Profile  
 
 Post subject: Re: Retro-Access Releases Dreamcast 15Khz/31Khz Scart/BNC Ca
PostPosted: Mon May 06, 2019 9:03 pm 


User avatar

Joined: 25 Dec 2013
Posts: 608
Location: Indiana
maxtherabbit wrote:

are there full attenuator networks to keep impedance matched? or just series resistors?


They are full networks. :wink:


Top
 Offline Profile  
 
 Post subject: Re: Retro-Access Releases Dreamcast 15Khz/31Khz Scart/BNC Ca
PostPosted: Tue May 07, 2019 12:40 am 


User avatar

Joined: 05 Mar 2018
Posts: 882
citrus3000psi wrote:
maxtherabbit wrote:

are there full attenuator networks to keep impedance matched? or just series resistors?


They are full networks. :wink:

Image


Top
 Offline Profile  
 
 Post subject: Re: Retro-Access Releases Dreamcast 15Khz/31Khz Scart/BNC Ca
PostPosted: Tue May 07, 2019 6:40 am 



Joined: 05 Jul 2016
Posts: 34
citrus3000psi wrote:
Yes, RGB max levels are right at 700mv.

The CSYNC also has the serration pulses so it works on the BVM D & A series monitors that lack the vcr button in 480p mode.


Does this mean that you don't need any Extron devices in your chain anymore when using Sony BVM D or A series and this cable. Or was that curve on top of screen partly because of Toro? I know that VCR mode fixed curve for PC Engine, Neo Geo MVS and Sega Master System but didn't help with Dreamcast + Toro. You needed Extron device with serr switch on in your chain. Hopefully you only need this cable now?


Top
 Offline Profile  
 
 Post subject: Re: Retro-Access Releases Dreamcast 15Khz/31Khz Scart/BNC Ca
PostPosted: Tue May 07, 2019 5:40 pm 



Joined: 21 Jul 2014
Posts: 64
Location: UK
citrus3000psi wrote:
maxtherabbit wrote:

are there full attenuator networks to keep impedance matched? or just series resistors?


They are full networks. :wink:


I guess you are taking about the RCA cables here citrus rather than the RGC offering?


Top
 Offline Profile  
 
 Post subject: Re: Retro-Access Releases Dreamcast 15Khz/31Khz Scart/BNC Ca
PostPosted: Tue May 07, 2019 8:47 pm 


User avatar

Joined: 05 Mar 2018
Posts: 882
EnragedWhale wrote:
citrus3000psi wrote:
maxtherabbit wrote:

are there full attenuator networks to keep impedance matched? or just series resistors?


They are full networks. :wink:


I guess you are taking about the RCA cables here citrus rather than the RGC offering?

we are talking about the Retro-Access cables, that citrus designed the PCB for


Top
 Offline Profile  
 
 Post subject: Re: Retro-Access Releases Dreamcast 15Khz/31Khz Scart/BNC Ca
PostPosted: Wed May 08, 2019 12:23 pm 


User avatar

Joined: 25 Dec 2013
Posts: 608
Location: Indiana
Decoryah wrote:
citrus3000psi wrote:

Does this mean that you don't need any Extron devices in your chain anymore when using Sony BVM D or A series and this cable. Or was that curve on top of screen partly because of Toro? I know that VCR mode fixed curve for PC Engine, Neo Geo MVS and Sega Master System but didn't help with Dreamcast + Toro. You needed Extron device with serr switch on in your chain. Hopefully you only need this cable now?


Yeah, no need for the extron box with the RA cable.


Top
 Offline Profile  
 
 Post subject: Re: Retro-Access Releases Dreamcast 15Khz/31Khz Scart/BNC Ca
PostPosted: Wed May 08, 2019 1:09 pm 


User avatar

Joined: 06 Mar 2006
Posts: 11836
Location: Germany
Quote:
Yeah, no need for the extron box with the RA cable.

that's really nice! If you don't mind me asking - how is this accomplished? Is there an active IC inside the cable to manage the serration pulses or is this done with a passive circuit?


Top
 Offline Profile  
 
 Post subject: Re: Retro-Access Releases Dreamcast 15Khz/31Khz Scart/BNC Ca
PostPosted: Wed May 08, 2019 1:32 pm 


User avatar

Joined: 25 Dec 2013
Posts: 608
Location: Indiana
Fudoh wrote:
Quote:
Yeah, no need for the extron box with the RA cable.

that's really nice! If you don't mind me asking - how is this accomplished? Is there an active IC inside the cable to manage the serration pulses or is this done with a passive circuit?


Its a passive circuit. There is a multivibrator ic that gets triggered during the vertical blank period.


Top
 Offline Profile  
 
 Post subject: Re: Retro-Access Releases Dreamcast 15Khz/31Khz Scart/BNC Ca
PostPosted: Wed May 08, 2019 6:25 pm 



Joined: 01 Jul 2017
Posts: 41
Fudoh wrote:
Quote:
Yeah, no need for the extron box with the RA cable.

that's really nice! If you don't mind me asking - how is this accomplished? Is there an active IC inside the cable to manage the serration pulses or is this done with a passive circuit?


That's really cool! I used a similar method, with a PIC as a software multi-vibrator so it can adapt to different line frequencies, in my Raspberry Pi hat. If you don't mind me asking, how long do you hold the sync line low before releasing it during VSYNC? I have it set to 75% of the line duration but some people were still reporting issues with BVMs.


Top
 Offline Profile  
 
 Post subject: Re: Retro-Access Releases Dreamcast 15Khz/31Khz Scart/BNC Ca
PostPosted: Wed May 08, 2019 7:15 pm 


User avatar

Joined: 20 May 2011
Posts: 1126
Location: Southern California
Oh wow, looks like this could be a smaller more compact replacement of my Toro (which I do find a bit bulky).
_________________
The Artcade blog


Top
 Offline Profile  
 
 Post subject: Re: Retro-Access Releases Dreamcast 15Khz/31Khz Scart/BNC Ca
PostPosted: Thu May 09, 2019 9:13 am 


User avatar

Joined: 12 Jul 2007
Posts: 5645
Location: Where the fish lives, WV
Hmmm....so, what will this do over the normal SCART cables?
I didn't know what the issues were to begin with.
_________________
My Collection: http://www.rfgeneration.com/cgi-bin/col ... Collection


Top
 Offline Profile  
 
 Post subject: Re: Retro-Access Releases Dreamcast 15Khz/31Khz Scart/BNC Ca
PostPosted: Thu May 09, 2019 12:51 pm 



Joined: 19 Jul 2017
Posts: 1427
evil_ash_xero wrote:
Hmmm....so, what will this do over the normal SCART cables?
I didn't know what the issues were to begin with.

A few things. First, normal SCART cables for the Dreamcast only bridge one video mode pin to get 15kHz RGBS out of the system. This cable (as well as the ones built by thefoo.83) include a mode switch that bridges/unbridges the second video mode pin to toggle 31kHz (480p) output, which can also be used to trick most 480i-only games into outputting at 480p.

Secondly, and building off the first point, the Dreamcast shuts off composite sync output when in 480p mode, meaning it only provides 480p in RGBHV, which is incompatible with SCART. This cable includes an inline sync combiner that will take that 480p RGBHV output and convert it to 480p RGBS so it's compatible with the SCART connection.

And, lastly, normal Dreamcast SCART cables are not built with fully-shielded coax, and would therefore be more susceptible to things like visual noise and audio hum/buzz.


Top
 Offline Profile  
 
 Post subject: Re: Retro-Access Releases Dreamcast 15Khz/31Khz Scart/BNC Ca
PostPosted: Thu May 09, 2019 1:11 pm 



Joined: 12 Sep 2018
Posts: 28
It’s worth saying a few other things:

480p is incompatible with SCART for *no good reason*. TVs with Scart sockets, that work with 480p in other modes will not accept 480p over Scart. It’s something to do with standards being set back in the day and manufacturers sticking to those standards. Or maybe it’s to do with making you buy a new TV with component inputs. I suspect the latter.

Most consoles with 480p capability will not output 480p over RGBS as a result of the above. Unless you modify them, that is.

Consoles that output vga can be made to do it externally, by combining the H+V lines. VGA allows for 480p mode so you can do this.

Good scalers ignore the standards that set RGBS over Scart at 480i (there’s no real reason for it after all!). OSSC and Framemeister work with 480p RGBS over Scart.

The 480p mode will not work on SCART compliant TVs.
The 480p mode will, however work on scalers and 480p compliant rgbs monitors. These are the solutions used in the USA, so, no worries!


Top
 Offline Profile  
 
 Post subject: Re: Retro-Access Releases Dreamcast 15Khz/31Khz Scart/BNC Ca
PostPosted: Thu May 09, 2019 1:50 pm 



Joined: 14 Aug 2017
Posts: 589
Yep, SCART connectors can pass anything along up to 1080i, right? They can also pass sync on green of course (PS2, some other consoles with mods), just need to set the monitor's sync accordingly.

BTW, I'm hoping that we'll also see a DE-15 option for this cable besides the SCART and BNC ones.


Top
 Online Profile  
 
 Post subject: Re: Retro-Access Releases Dreamcast 15Khz/31Khz Scart/BNC Ca
PostPosted: Thu May 09, 2019 4:27 pm 



Joined: 19 Jul 2017
Posts: 1427
fernan1234 wrote:
Yep, SCART connectors can pass anything along up to 1080i, right? They can also pass sync on green of course (PS2, some other consoles with mods), just need to set the monitor's sync accordingly.

BTW, I'm hoping that we'll also see a DE-15 option for this cable besides the SCART and BNC ones.

Yes, SCART can physically transport pretty much anything up to 1080p (although analogue 1080p is not widely supported; Xbox 360 and PS3 can manage it), probably slightly more; but SCART devices generally don't support more than 480i/576i over RGBS.

Some devices can transmit 31kHz+ using RGsB and/or YPbPr over SCART, but I think few video processors and displays will actually know what to do with those signals, and they probably ignore RGsB/YPbPr, because they [purposefully] do not send any sync signal on the sync line.

I've read a rumor or two that suggests that 31kHz+ signals sent to a 15kHz-only display can damage that display, which might explain why the PS2 won't output 31kHz+ RGBS and why the Xbox, Xbox 360 (I think), PS3, and Dreamcast purposefully disable 31kHz+ when using a SCART cable, though you could still send 31kHz+ to one of these displays with YPbPr, which wasn't addressed.


Top
 Offline Profile  
 
 Post subject: Re: Retro-Access Releases Dreamcast 15Khz/31Khz Scart/BNC Ca
PostPosted: Thu May 09, 2019 5:37 pm 


User avatar

Joined: 05 Mar 2018
Posts: 882
Everyone needs to remember that the "sync line" on SCART is not a sync line at all. By the spec, it is a composite video line that just so happens to be used (secondarily) for sync in the context of RGB SCART

There is no such thing as 31kHz CVBS so not tolerating 31kHz CSYNC in its stead is no surprise


Top
 Offline Profile  
 
 Post subject: Re: Retro-Access Releases Dreamcast 15Khz/31Khz Scart/BNC Ca
PostPosted: Fri May 10, 2019 1:33 am 


User avatar

Joined: 12 Jul 2007
Posts: 5645
Location: Where the fish lives, WV
So, is this useful (other than the shielding) if I just have my DC hooked into a 480i TV?
Any picture improvements?
_________________
My Collection: http://www.rfgeneration.com/cgi-bin/col ... Collection


Top
 Offline Profile  
 
 Post subject: Re: Retro-Access Releases Dreamcast 15Khz/31Khz Scart/BNC Ca
PostPosted: Fri May 10, 2019 1:43 am 


User avatar

Joined: 20 Jul 2017
Posts: 457
If you can't use VGA mode (480p) there aren't any compelling reason to get this, unless your current cable is terrible quality and you have a noisy image.


Top
 Offline Profile  
 
 Post subject: Re: Retro-Access Releases Dreamcast 15Khz/31Khz Scart/BNC Ca
PostPosted: Fri May 10, 2019 2:01 am 


User avatar

Joined: 30 Aug 2016
Posts: 166
Location: Burlington, Vermont, USA
evil_ash_xero wrote:
So, is this useful (other than the shielding) if I just have my DC hooked into a 480i TV?
Any picture improvements?

This product will not help you in any way, if your display is limited to 480i.
_________________
-the Goat
Heliopause Heavy Industries :: video game console repairs and modifications


Top
 Offline Profile  
 
Display posts from previous:  Sort by  
Post new topic Reply to topic  [ 100 posts ]  Go to page 1, 2, 3, 4  Next

All times are UTC


Who is online

Users browsing this forum: DejahThoris, fernan1234, Google [Bot], tongshadow and 12 guests


You cannot post new topics in this forum
You cannot reply to topics in this forum
You cannot edit your posts in this forum
You cannot delete your posts in this forum

Search for:
Jump to:  
Space Pilot 3K template by Jakob Persson
Powered by phpBB © 2000, 2002, 2005, 2007 phpBB Group