MiSTerFPGA Y/C Out Module (Direct - S-Video / Composite Output) - Update

Discussion about displays and related hardware including MiSTer filters and video settings.
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MiSTerFPGA Y/C Out Module (Direct - S-Video / Composite Output) - Update

Unread post by MikeS1 »

Hi everyone, I just wanted to create a new post around the work to generate Y/C straight out of the MiSTer and let everyone know why I created it, how it works, how many cores have this function and it getting added to the framework.

UPDATE
Y/C and Composite have now been added to the MiSTer framework, to enable the feature please ensure the following are changed in the ini file. The cores are aggressively being updated to include the new framework so please be patient or notify me or the core developer if there is one that's been missed.

Code: Select all

;ypbpr=0                   ;  (obsolete. see vga_mode)
vga_mode=svideo      ; supported modes: rgb, ypbpr, svideo, cvbs. rgb is default.
ntsc_mode=0             ; Only for S-Video and CVBS vga_mode. 0 - normal NTSC, 1 - PAL-60, 2 - PAL-M.

CVBS is not recommended and will not work with any passive or active adapters well. It may work if you are using an external scalar for HDMI.

Sync on Green - disable - (If using an external passive or active adapter)

Dot Crawl - A yc.txt file is now required in the MiSTer root folder to provide accurate reference NTSC / PAL frequencies for each core (This is required to eliminate dot crawl). If the core displays any signs of dot crawl, this may be missing or there may be a typo in this file. If you do notice any issues please send a message to myself or the core developer to see if it can be addressed. (NES defaults with dot crawl as it exists on real hardware, you can change that in the yc.txt file)

Here is an example of what you would see for the SNES, where a new reference frequency (Phase Increment) value is required any time the framerate changes or interlaced mode was toggled:

Code: Select all

SNES_60.1=91625968981
SNES_60.0i=91625968981

Note: Y/C will still work if these values are not in the yc.txt file but they are auto calculated within the framework and will have dot crawl issues, so it is recommended that they be added.

Quick reference link for anyone looking for breakout board designs, cores and sample code:
https://github.com/MikeS11/MiSTerFPGA_YC_Encoder

A bit of History

Back in 2021 I found an old commodore 1702 monitor and picked it up to use in my retro collection. To my surprise, I didn’t know how good the monitor looked compared to my 27 Sony Trinitron TV and when I found out I didn’t have an easy way to connect my MiSTer to the commodore monitor, I created an external encoder using an Analog Digital AD724 encoder with a trim capacitor knowing there were issues with dot crawl.

While the external encoder worked, I found the trim capacitor to be a tiresome task to try to reduce any dot crawl when switching cores, some cores could never remove all the dot crawl, and after a while the trim capacitor failed over wear and tear. I gave this up after a few months and decided to try to write a module to modulate the colour straight from the core.
I started looking at writing the module in Verilog in early 2022 and after a couple months, multiple iterations and support from Kitrinx, Grabulosaure and Paulb-nl I built a functional module that was modular and could be added to the framework if a developer enabled it. Since then I’ve created custom Y/C versions of most cores; this was more or less a challenge to get through the tuning phase of ironing out any dot crawl and as of writing this, there are roughly 140 cores.

How the Y/C Module Works

How the module works is fairly straightforward if you’ve read the book: “Video Demystified: A Handbook for the Digital Engineer”.
Luma and Chroma are generated using the YUV601 colorspace where:

  • Y (Luma) = 0.299R´ + 0.587G´ + 0.114B´

  • U = 0.492(B´ – Y)

  • V = 0.877(R´ – Y)

  • R´ – Y = 0.701R´ – 0.587G´ – 0.114B´

  • B´ – Y = –0.299R´ – 0.587G´ + 0.886B´

  • C (Chroma) = U sin ωt + V cos ωt

Note 1: V is flipped every other line when PAL is enabled, as well a 90% phase shift in the colorburst.

Note 2: Colorburst targets the standard NTSC / PAL specifications, where they are 9-10 cycles and roughly 280-300mV in magnitude. Many consoles will vary in magnitude and may be something that I make flexible in the future, though the impacts to the image are negligible.

Fundamentally, the Y/C module has 3 inputs, and is driven by the cores CLK_VIDEO.

  1. A Phase Increment Value – Used to create the 3.579 Mhz / 4.43 Mhz NTSC or PAL colorburst and chroma signals.

  2. A Colorburst Length – A colorburst start and end value that is dependent on the CLK_VIDEO.

  3. PAL Enable – Switches the Chroma modulation to the PAL standard.

Generating 3.579 Mhz

Because the module is using the CLK_VIDEO clock of the core, the sample rate of the NTSC reference signal is limited to the input clock. E.g 42.954544 Mhz from the NES / SNES core means 12 samples per cycle to generate one fundamental frequency of 3.579 Mhz.

Since each core has a different video clock and they are more likely not to be an exact multiple of the NTSC / PAL frequencies, direct digital synthesis was used to generate the reference frequency at any input frequency.

sinewave1.png
sinewave1.png (8.22 KiB) Viewed 13164 times

The Phase Accumulator

The phase accumulator is a 40 bit register where the 8 bits at [39:32] are the integer component of the accumulator and the following 32 bits are the fractional component.

Simply at 3.579 Mhz a 40 bit register should give an accuracy of 0.00002 Hz. I initially had a 32 bit phase increment with an accuracy of 0.005Hz but it still had problems with keeping its frequency locked and had some drift overtime.

The calculation to create the phase accumulator is:

(NTSC Ref * 240) / CLK_VIDEO
Example: Arcade Cores with a 48 Mhz CLK_VIDEO
= (3.579545 * 240) / 48
= 81994819784

Note 1: While this calculation will get the module functional, some cores may also require some additional tuning to remove any dot crawl when using composite. E.g. Vball tuned is 81995085016 and removes any dot crawl artifacts. There is a Test_Pattern_YC core that provides an example of the tuning logic.

Note 2: There is a limitation seen when you start to drive the Y/C module with frequencies under 30 Mhz, surprisingly you can still drive the module at 20 Mhz, but artifacts will be visible to some extent. (This is completely avoided at higher frequencies)

Example Source (Emu): Vball Arcade

The emu module requires the following, where there are 4 parameters to be modified:

Code: Select all

`ifdef MISTER_ENABLE_YC   // Old Code Reference
    parameter NTSC_REF = 3.579545;  
parameter PAL_REF = 4.43361875; localparam [6:0] COLORBURST_START = (3.7 * (CLK_VIDEO_NTSC/NTSC_REF)); localparam [9:0] COLORBURST_NTSC_END = (9 * (CLK_VIDEO_NTSC/NTSC_REF)) + COLORBURST_START; localparam [9:0] COLORBURST_PAL_END = (10 * (CLK_VIDEO_PAL/PAL_REF)) + COLORBURST_START; // Modified Variables parameter CLK_VIDEO_NTSC = 48; // Must be filled E.g XX.XXX Hz parameter CLK_VIDEO_PAL = 48; // Must be filled E.g XX.XXX Hz localparam [39:0] NTSC_PHASE_INC = 40'd81995085016; // ((NTSC_REF**2^40) / CLK_VIDEO_NTSC); localparam [39:0] PAL_PHASE_INC = 40'd0; // ((PAL_REF*2^40) / CLK_VIDEO_PAL) ; assign CHROMA_PHASE_INC = PALFLAG ? PAL_PHASE_INC : NTSC_PHASE_INC; assign YC_EN = status[22]; assign PALFLAG = 0; // if applicable, Change the status to match your configuration. assign COLORBURST_RANGE = {COLORBURST_START, COLORBURST_NTSC_END, COLORBURST_PAL_END}; `endif

Cores Available:
There are currently 20 Console cores, 11 PC cores and 119 Arcade cores that are available.

https://github.com/MikeS11/MiSTerFPGA_Y ... C%20Builds

cores1.png
cores1.png (115.13 KiB) Viewed 13164 times

I’ve spent months tuning most of the cores available so they have Y/C out with no dot crawl for both NTSC and PAL systems. The tuned values can be found here for reference: https://docs.google.com/spreadsheets/d/ ... sp=sharing

Display Methods
I would first check out the guide at: https://mister-devel.github.io/MkDocs_M ... by-mikes11
If you can hack up a cheap cable for S-Video, you really don’t need anything else, but if you’re using composite, you will need to add in a luma trap.

Custom Breakout Boards (Passive / Active Options)

Alternatively, I’ve built two different breakout boards, one is a fairly cheap passive board with a luma trap. The other is an active breakout board with an amplifier (THS7374) IC as well as two modes that make sure the voltages match NTSC spec if you're connected through the Analog IO board or Direct Video.

Details on the breakout boards can be found here:

https://github.com/MikeS11/MiSTerFPGA_Y ... t%20Boards

BreakoutBoards1.png
BreakoutBoards1.png (172.06 KiB) Viewed 13164 times

Adding the Y/C Module to the Framework

A lot have asked if this will be added to the framework in the future and I believe there is good hope to have this added to the framework in the future. The module is compact and modular and I’ve tried to make it as easy as possible to integrate.
A lot of the leg work was developing a list of “tuned” values for the cores, and that’s mostly complete now.
I’ve also forked the MiSTer Main / Template sources to show how the Y/C module can be integrated.

MiSTer Main:
Adding a yc_out toggle to the ini file to activate the Y/C module:
https://github.com/MikeS11/Main_MiSTer/ ... bb2f4641be

MiSTer Template:
Adding Y/C to the MiSTer Template: https://github.com/MikeS11/Template_MiS ... fcb65b9f90
Note: The current module does not use main to look for the flag in the ini file, it's triggered through the menu options. E.g Video Signal - (RGBS/YPbPr or Y/C)

Waiting2.png
Waiting2.png (44.71 KiB) Viewed 13164 times

Patiently Waiting

Learnings from the Process

Timing is important….

When calculating the U / V values I initially didn't account for the delays in the blue and red signals, which was really hard to notice until you look at the colorbleeding.

Learnings1.png
Learnings1.png (145.02 KiB) Viewed 13164 times

Rainbowing and Luma traps….

Composite is bad, but there are a lot of CRT TV’s in North America which only have composite as an option. If you can get away with S-Video, I would go down that path for Y/C. But in the case you want that blurry retro feel, a luma trap is a necessity and getting it right is a bit of a pain in the ass to get closer to 100% acceptance. Note the subtle change from the passive breakout board to active below.. That little difference which took months to get was at least worth it to me :). But even just a simple hack of a 10uH inductor / 200 pF cap into luma cable works wonders.

There are a lot of ways to go abouts doing it but a passive second order LC filter can make really good improvements.

Here is composite without a luma trap in a worst-case scenario Sonic on the Genesis

No_Luma1.png
No_Luma1.png (32.77 KiB) Viewed 13164 times

This is the same frame with a luma trap using the passive / active breakout boards as well as an external encoder:

LumaTrap1.png
LumaTrap1.png (216.1 KiB) Viewed 13164 times

Most External encoders have rainbowing issues as well but they are harder to pin down because of the excessive dot crawl to mask it.

Direct Video
Generating Chroma through an VGA to HDMI converter works just as it would through the Analog IO board though there are some caveats. A sync needs to be added to the luma signal, and the ADV7513, which transmits the HDMI signal, creates a dead zone in the RGB signal where the H / V syncs are transmitted. This is through the data enable (DE) flag that gets sent to the ADV7513.

This is not an issue for the composite signal because the chroma and luma signals are combined but S-Video can have the saturation thrown off slightly because of the notch in the signal. I’ve not noticed an issue with my consumer televisions, but I do have to slightly adjust the chroma on my PVM, and the 1702 monitor has a hard time locking onto the color signal.

Simply, there is no problem if you're using composite, and there shouldn't be a problem if you have a consumer CRT, but some of the niche monitors may have compatibility issues. E.g a PVM will need to dial the chroma back slightly.

There is probably a way to fix this through the ADV7513, but I've not found a way to fix this little bug.

DV_DE_Bug1.png
DV_DE_Bug1.png (140.58 KiB) Viewed 13164 times

Lastly

I still cant stress enough the amazing support from the community and though I probably annoyed many of you out there with stupid questions, I cant thank everyone enough :). I'm hoping to take some time now to try to port some old MiST cores over to MiSTer, starting with Nova 2001 and Raiders5.

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Re: MiSTerFPGA Y/C Out Module (Direct - S-Video / Composite Output) - Update

Unread post by aberu »

It's truly been awesome talking with you about this project ever since you got started. Thank you for proving it can be done and putting in this huge amount of work in getting it to where it is (which is to say, Complete! :) ).
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Re: MiSTerFPGA Y/C Out Module (Direct - S-Video / Composite Output) - Update

Unread post by akeley »

Thank you for continuing to work on the hardware side and updating the cores themselves. Huge task which is greatly appreciated.

Do you know of anybody selling, or planning to sell these luma trap boards?

Also, as a side note, composite isn't really "bad", at least not when it comes to retro games. Let's just say it's different :)
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Re: MiSTerFPGA Y/C Out Module (Direct - S-Video / Composite Output) - Update

Unread post by rickdangerous »

Let's test this. If works great I'm happy to support Mike on production, sales and core updates :) thx

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Re: MiSTerFPGA Y/C Out Module (Direct - S-Video / Composite Output) - Update

Unread post by Longtime4321 »

Of course, the day after I get my composite adapter from Ultimate Mister -_- . I'd imagine your guys's adapter is better though
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Re: MiSTerFPGA Y/C Out Module (Direct - S-Video / Composite Output) - Update

Unread post by shertz »

So I exclusively play through s-video using a component cable through analog IO board. Picture looks great. Will I need one of those adapters?
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Re: MiSTerFPGA Y/C Out Module (Direct - S-Video / Composite Output) - Update

Unread post by MikeS1 »

shertz wrote: Wed Oct 05, 2022 2:18 am So I exclusively play through s-video using a component cable through analog IO board. Picture looks great. Will I need one of those adapters?
No not at all, if your running S-Video on the analog IO board I would stay with what you got right now. The larger benefit is on composite.
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Re: MiSTerFPGA Y/C Out Module (Direct - S-Video / Composite Output) - Update

Unread post by LamerDeluxe »

Thanks for all the awesome work on this, I had never expected it to be possible. Good to see the new board design, looking forward to finally being able to buy a luma trap adapter that works. Hopefully it will be an official part of MiSTer soon.
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Re: MiSTerFPGA Y/C Out Module (Direct - S-Video / Composite Output) - Update

Unread post by barfood »

Amazing work Mike, thanks a ton!

Sidenote while on the topic of YC cores, I had an issue previously with getting mras for YC arcade cores. I haven't looked into this issue of mine in a while, but if someone has tips on where/how to download, I'm a taker.

Thanks again, this work is incredibly appreciated!
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Re: MiSTerFPGA Y/C Out Module (Direct - S-Video / Composite Output) - Update

Unread post by MikeS1 »

barfood wrote: Wed Oct 05, 2022 12:04 pm Amazing work Mike, thanks a ton!

Sidenote while on the topic of YC cores, I had an issue previously with getting mras for YC arcade cores. I haven't looked into this issue of mine in a while, but if someone has tips on where/how to download, I'm a taker.

Thanks again, this work is incredibly appreciated!
For now, the best way to do it is to create separate folders and copy all the mras from the arcade folder into something like _YCArcades then creates a cores folder and copy all the y/c cores there e.g _YCArcades/cores

When I add a new core, I normally copy the mras from the release folder so I at least know that I have a yc core for it. But that's way more work :)
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Re: MiSTerFPGA Y/C Out Module (Direct - S-Video / Composite Output) - Update

Unread post by MikeS1 »

rickdangerous wrote: Tue Oct 04, 2022 11:27 am Let's test this. If works great I'm happy to support Mike on production, sales and core updates :) thx
That would be awesome ! Please reach out if you have any questions.

I posted a video of composite today as well just running through some cores. https://youtu.be/ppve_BaHVtI
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Re: MiSTerFPGA Y/C Out Module (Direct - S-Video / Composite Output) - Update

Unread post by rickdangerous »

Have ordered some PCBs will back to you soon.

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Re: MiSTerFPGA Y/C Out Module (Direct - S-Video / Composite Output) - Update

Unread post by AmintaMister »

rickdangerous wrote: Tue Oct 11, 2022 3:35 pm Have ordered some PCBs will back to you soon.
I'm interested!
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Re: MiSTerFPGA Y/C Out Module (Direct - S-Video / Composite Output) - Update

Unread post by eobet »

This is most likely a very ignorant question, but could future Mister Analog IO boards have this "luma trap" thing built in, so you don't have to use a dongle?
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Re: MiSTerFPGA Y/C Out Module (Direct - S-Video / Composite Output) - Update

Unread post by antoniovillena »

As promised I've created an adapter based on MikeS1 schematics. It has the same size of my other adapter, so I can reuse the cases. Sale link here:

https://www.antoniovillena.es/store/pro ... e-adapter/

I have created these 2 videos for PAL and NTSC using this adapter:



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Re: MiSTerFPGA Y/C Out Module (Direct - S-Video / Composite Output) - Update

Unread post by AmintaMister »

antoniovillena wrote: Tue Oct 18, 2022 1:41 pm

As promised I've created an adapter based on MikeS1 schematics. It has the same size of my other adapter, so I can reuse the cases. Sale link here:

Bought!

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Re: MiSTerFPGA Y/C Out Module (Direct - S-Video / Composite Output) - Update

Unread post by Dougdoesnt »

Is there a pinout diagram somewhere that I can use to build a custom cable? I have a VGA cable and a s-video cable to act as donors, just not sure about how to arrange the mod.
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Re: MiSTerFPGA Y/C Out Module (Direct - S-Video / Composite Output) - Update

Unread post by thorr »

Does this allow color artifacting to work giving more colors? Does the color artifacting work with both S-Video and Composite, but not Component? Does the color artifacting work with PCXT in CGA mode (not using the core's emulation of the color artifacting)? I am just trying to understand if there is any benefit over component video. Thanks!
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Re: MiSTerFPGA Y/C Out Module (Direct - S-Video / Composite Output) - Update

Unread post by Dougdoesnt »

Dougdoesnt wrote: Mon Oct 31, 2022 4:38 pm Is there a pinout diagram somewhere that I can use to build a custom cable? I have a VGA cable and a s-video cable to act as donors, just not sure about how to arrange the mod.
I got in touch with Mike on discord and he instructed me on how to build the cable:

VGA Pin #1 (Red) connects to SVIDEO Chroma (NW)
VGA Pin #2 (Green) connects to SVIDEO Luma (NE)
VGA Pin #5 (GRND) connects to SVIDEO both grounds (SW & SE)

I assembled a cable and double checked my continuity and I believe I built it correctly.

When I try to use the cable, the Main MiSTer menu appears on the screen, but it is very wavy and jittery. When I load any core (vanilla or YC) it looks like it has lost sync. The image rolls vertically and if I have a YC core loaded and switch from RGBs to YC output, I lose the image completely and there's just artifacts strobing on the screen.

It seems like I have a sync problem... I've tried all the different combinations of SOG and composite sync, and all have exhibited these same symptoms. Is there something that I am missing? Could this be a symptom of not building my cable properly?
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Re: MiSTerFPGA Y/C Out Module (Direct - S-Video / Composite Output) - Update

Unread post by jd213 »

I was thinking about making my own cable too, but I've got enough projects to finish as it is.

I already have a VGA to component adapter, so I just need a component to S-Video adapter. Is there one on Amazon or somewhere? I found one, but it's a "7-pin" S-video adapter, so doesn't look like it would work.
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Re: MiSTerFPGA Y/C Out Module (Direct - S-Video / Composite Output) - Update

Unread post by Dougdoesnt »

jd213 wrote: Wed Nov 02, 2022 7:33 pm I was thinking about making my own cable too, but I've got enough projects to finish as it is.

I already have a VGA to component adapter, so I just need a component to S-Video adapter. Is there one on Amazon or somewhere? I found one, but it's a "7-pin" S-video adapter, so doesn't look like it would work.
I cut a VGA cable and a svideo cable in halves and soldered them together. So I can't help you with the adapter you would want. It would need to be "2 RCA to S-Video" where one of the RCAs goes to the chroma pin and the other RCA goes to the luma pin. I'm not sure if an adapter like that actually exists- I can't imagine a use case outside our wacky hobby.

If you find one, let me know!
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Re: MiSTerFPGA Y/C Out Module (Direct - S-Video / Composite Output) - Update

Unread post by jd213 »

Thanks, I found a couple different cables on Amazon with either BNC or RCA connectors on one end and a 4-Pin S-Video connector on the other, like this one:
https://www.amazon.com/gp/product/B0923RLTXQ

So that would probably work in combination with one of my VGA to BNC adapters, but then I remembered I had an extra D-SUB 15 screw terminal kit in my basement, like this one:
https://www.amazon.com/dp/B07F9S61QT/

So I wired that up with an old JVC S-Video cable I had lying around. Not sure if it makes a difference, but I wired the ground pins to 6 and 7 separately instead of tying them together. See the RetroRGB page:
https://www.retrorgb.com/how-to-hook-up ... osite.html

So hopefully this works, but I've got to DL the Y/C cores and put them on my SD card first, and I have other stuff to do tonight so it will have to wait until tomorrow before I test it.
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Re: MiSTerFPGA Y/C Out Module (Direct - S-Video / Composite Output) - Update

Unread post by LamerDeluxe »

I just came across an old VGA to S-Video and composite cable, which probably belonged to my Matrox G400 videocard. I tested the contacts and it correctly connects the S-Video signals to pin 1 and 2. The composite connector connects to pin 4, so it won't work for that. This cable is marked 'BOC-TV-OUT0'. I see lots of similar cables can still be bought.
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Re: MiSTerFPGA Y/C Out Module (Direct - S-Video / Composite Output) - Update

Unread post by jd213 »

Dougdoesnt wrote: Wed Nov 02, 2022 3:43 pm
Dougdoesnt wrote: Mon Oct 31, 2022 4:38 pm Is there a pinout diagram somewhere that I can use to build a custom cable? I have a VGA cable and a s-video cable to act as donors, just not sure about how to arrange the mod.
I got in touch with Mike on discord and he instructed me on how to build the cable:

VGA Pin #1 (Red) connects to SVIDEO Chroma (NW)
VGA Pin #2 (Green) connects to SVIDEO Luma (NE)
VGA Pin #5 (GRND) connects to SVIDEO both grounds (SW & SE)

I assembled a cable and double checked my continuity and I believe I built it correctly.

When I try to use the cable, the Main MiSTer menu appears on the screen, but it is very wavy and jittery. When I load any core (vanilla or YC) it looks like it has lost sync. The image rolls vertically and if I have a YC core loaded and switch from RGBs to YC output, I lose the image completely and there's just artifacts strobing on the screen.

It seems like I have a sync problem... I've tried all the different combinations of SOG and composite sync, and all have exhibited these same symptoms. Is there something that I am missing? Could this be a symptom of not building my cable properly?
I ended up having the exact same sync problems you did, and I also tried just about all ini setting and SOG switch combinations (except I didn't think to try turning composite sync off). Used a multimeter to verify that all the pins were wired correctly and that there were no shorts, so I dunno what the problem could be. I used different VGA pins for ground and kept them separate, but if you kept them together and had the same problem, that's probably not the cause.

Guess I'll have to try a BNC to S-Video adapter or wait for Mike's breakout board...
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Re: MiSTerFPGA Y/C Out Module (Direct - S-Video / Composite Output) - Update

Unread post by passballtotucker »

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Looks like Antonio’s adapter still has some issues. I’ve only noticed it in the PlayStation core. Maybe it’s an issue with that core. I haven’t noticed any color problems on other cores.
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Re: MiSTerFPGA Y/C Out Module (Direct - S-Video / Composite Output) - Update

Unread post by LamerDeluxe »

passballtotucker wrote: Thu Nov 10, 2022 3:51 am

Looks like Antonio’s adapter still has some issues. I’ve only noticed it in the PlayStation core. Maybe it’s an issue with that core. I haven’t noticed any color problems on other cores.

Is that Y/C or composite?

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Re: MiSTerFPGA Y/C Out Module (Direct - S-Video / Composite Output) - Update

Unread post by passballtotucker »

LamerDeluxe wrote: Thu Nov 10, 2022 8:22 am
passballtotucker wrote: Thu Nov 10, 2022 3:51 am

Looks like Antonio’s adapter still has some issues. I’ve only noticed it in the PlayStation core. Maybe it’s an issue with that core. I haven’t noticed any color problems on other cores.

Is that Y/C or composite?

It’s composite. After some trouble shooting, I’m found that it’s not Antonio’s adapter and likely not the core either. I think there’s something on my end that’s wrong. I’m still trying to figure it out. If anyone else experienced this please let me know.

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Re: MiSTerFPGA Y/C Out Module (Direct - S-Video / Composite Output) - Update

Unread post by MikeS1 »

Yeah, I tried multiple versions of the PSX core including one from today, I dont have this issue on any of my boards nor CRT's. As we chatted on discord, it could come down to some type of odd settings or potentially the IO board has a minor issue causing the chroma modulation to be off slightly.
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Re: MiSTerFPGA Y/C Out Module (Direct - S-Video / Composite Output) - Update

Unread post by trisk »

antoniovillena wrote: Tue Oct 18, 2022 1:41 pm

As promised I've created an adapter based on MikeS1 schematics. It has the same size of my other adapter, so I can reuse the cases. Sale link here:

Is this board implementing the active or passive board design for composite? Either the video quality on YouTube looks great!

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Re: MiSTerFPGA Y/C Out Module (Direct - S-Video / Composite Output) - Update

Unread post by passballtotucker »

passballtotucker wrote: Thu Nov 10, 2022 6:27 pm
LamerDeluxe wrote: Thu Nov 10, 2022 8:22 am
passballtotucker wrote: Thu Nov 10, 2022 3:51 am

Looks like Antonio’s adapter still has some issues. I’ve only noticed it in the PlayStation core. Maybe it’s an issue with that core. I haven’t noticed any color problems on other cores.

Is that Y/C or composite?

It’s composite. After some trouble shooting, I’m found that it’s not Antonio’s adapter and likely not the core either. I think there’s something on my end that’s wrong. I’m still trying to figure it out. If anyone else experienced this please let me know.

Ok this is resolved. I got a new io board and everything is fine now.

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