Original analog video without I/O board? Possible!

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Re: Original analog video without I/O board? Possible!

Postby pbsk8 » Fri Dec 06, 2019 1:28 pm

I am thinking about buying a de10 nano + 128 mb ram without io board

I have a crt 21'' with composite and s-video input, is there a way to connect the mister fpga to it with an adapter? Because the issue I think is how to get audio from the tv.

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Re: Original analog video without I/O board? Possible!

Postby paulbnl » Fri Dec 06, 2019 4:20 pm

mrchrister wrote:Not sure I understand this.. so input lag is slightly higher using direct video than through the IO board, correct?


This is answered in this topics first post. Hint: incorrect.

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Re: Original analog video without I/O board? Possible!

Postby mrchrister » Fri Dec 06, 2019 5:07 pm

Thanks for pointing this out. I think I will be good with not getting the IO board in this case... The only thing I would be missing out on are Arcade cores which at this point don't support direct video (to my understanding)
I talked to jotego, who is creating arcade cores for the MISTer, here is what he said when I asked if he plans for support of Direct Video in the future:

I haven’t really tried that option with my cores. According to Sorgelig, the MiSTer curator, the option should be transparent to the cores without any need for core modification. But there may be some need to tweak other parameters in the INI file related to video.

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Re: Original analog video without I/O board? Possible!

Postby MottZilla » Fri Dec 06, 2019 9:13 pm

pbsk8 wrote:I am thinking about buying a de10 nano + 128 mb ram without io board

I have a crt 21'' with composite and s-video input, is there a way to connect the mister fpga to it with an adapter? Because the issue I think is how to get audio from the tv.


You'll need a RGB to NTSC Encoder to convert the RGB signal to S-Video. The MiSTer's analog video output is either RGB with HV Sync or RGB with Composite Sync. There is no direct S-Video or Composite Video. There is Component (YPbPr) Video output if your TV supports that.

As for audio, some of the HDMI to VGA adapters if you go that route have a standard stereo audio connector that could be plugged into a pair of speakers.

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Re: Original analog video without I/O board? Possible!

Postby Vicosku » Wed Dec 11, 2019 4:20 am

I accidentally found a Tripp-Lite P131-06N I bought years ago while rummaging around, so I gave it a try. It can use the hdmi_limited=0 setting for full 0-255 range, unlike the Ugreen model.

The part I was most pleased about is that the analog audio output has less noise than the Moread and Ugreen adapters that have been mentioned in this thread. On my headphones and cheap little amp, there is a bit of static on the Ugreen at high volumes. The Moread is a bit worse, as there is audible noise in the right channel at normal volumes, at least on the one I got. The Tripp-Lite remains completely silent to my ears when I max out my amp. It may be worth checking out if this is something that's important to you.

It does have an odd behavior the others don't though. There is a bit of a buzz when changing cores or loading a game. I need to test some more, but I tried some Sega CD stuff tonight and the buzzing doesn't seem to occur during gameplay or loading CD image data.

The bad thing is that they cost around $30-$35 USD. This is more than triple that of some of the other adapters being discussed. It's also double the height of the Ugreen and a bit longer. I haven't opened it up to have a look inside.

https://www.tripplite.com/hdmi-to-vga-w ... 0p~P13106N

Edit: None of the load buzzing I mentioned happened tonight. That may have been before I changed the hdmi_limited option from 2 to 0.

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Re: Original analog video without I/O board? Possible!

Postby zomgugoff » Thu Dec 12, 2019 12:43 pm

Is there any chance we could get audio through the I/O board? I use the optical audio out and I can't do that with a VGA converter.

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Re: Original analog video without I/O board? Possible!

Postby Sorgelig » Thu Dec 12, 2019 1:12 pm

audio is always available through I/O board.

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Re: Original analog video without I/O board? Possible!

Postby Stremon » Thu Dec 12, 2019 1:27 pm

Is anyone else having trouble displaying the main menu with direct video (15kHz RGBs)?
It's weird because all cores that support direct video work perfectly, with on screen menu and all, only the main menu doesn't work.
It seems my PVM can't get a proper sync to work with, I can only see some white line shaking on screen, but no coherent image.
I got one of those tailed HDMI to VGA adapter with audio out, but I couldn't check the chipset since I don't know how to open it without breaking it.
I use a VGA switch to change between the IO VGA and the adapter, but it's really annoying to not be able to use only one.

Also, I understood direct video should have better colors than the IO board VGA, but knowing the limited color space of most old gaming hardware, is there any core that is actually getting a true benefits from it?

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Re: Original analog video without I/O board? Possible!

Postby MottZilla » Fri Dec 13, 2019 2:58 am

Stremon wrote:Is anyone else having trouble displaying the main menu with direct video (15kHz RGBs)?
It's weird because all cores that support direct video work perfectly, with on screen menu and all, only the main menu doesn't work.
It seems my PVM can't get a proper sync to work with, I can only see some white line shaking on screen, but no coherent image.
I got one of those tailed HDMI to VGA adapter with audio out, but I couldn't check the chipset since I don't know how to open it without breaking it.
I use a VGA switch to change between the IO VGA and the adapter, but it's really annoying to not be able to use only one.

Also, I understood direct video should have better colors than the IO board VGA, but knowing the limited color space of most old gaming hardware, is there any core that is actually getting a true benefits from it?


Did you make sure both your main MiSTer file and Menu.rbf files are completely up to date? I used Direct Video before I had my I/O Board and the menu displayed fine. If you have the I/O board I don't see any reason to use Direct Video since compatibility is less than from the I/O board.

The I/O board RGB output has 5 bits per channel for 15-bit color I believe. That's enough for around 32,768 colors. Some system examples:

SNES 15-Bit RGB
NeoGeo 15-Bit RGB
Gameboy Color 15-Bit RGB
Master System 6-Bit RGB
Genesis 9-Bit RGB
Game Gear 12-Bit RGB
32X 15-Bit RGB
TurboGrafx 15-Bit RGB

The Playstation is capable of outputting 24-Bit "True Color" RGB but this is not used in gameplay, I think it's only for FMV or possibly still frame artwork. Otherwise Playstation is again 15-Bit RGB.

I'm not as familiar with the computer cores and if any of them are capable of beyond 15-Bit RGB.

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Re: Original analog video without I/O board? Possible!

Postby zomgugoff » Fri Dec 13, 2019 4:22 am

MottZilla wrote:The I/O board RGB output has 5 bits per channel for 15-bit color I believe. That's enough for around 32,768 colors. Some system examples:

SNES 15-Bit RGB
NeoGeo 15-Bit RGB
Gameboy Color 15-Bit RGB
Master System 6-Bit RGB
Genesis 9-Bit RGB
Game Gear 12-Bit RGB
32X 15-Bit RGB
TurboGrafx 15-Bit RGB

The Playstation is capable of outputting 24-Bit "True Color" RGB but this is not used in gameplay, I think it's only for FMV or possibly still frame artwork. Otherwise Playstation is again 15-Bit RGB.

I'm not as familiar with the computer cores and if any of them are capable of beyond 15-Bit RGB.


Per the OP, the I/O board outputs 6-bit, VGA adapter outputs 8-bit. It's also says the video (and audio) are better than the I/O board. IIRC, the idea was the color reproduction would be more accurate with the extra color bits.

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Re: Original analog video without I/O board? Possible!

Postby MottZilla » Fri Dec 13, 2019 7:57 am

zomgugoff wrote:Per the OP, the I/O board outputs 6-bit, VGA adapter outputs 8-bit. It's also says the video (and audio) are better than the I/O board. IIRC, the idea was the color reproduction would be more accurate with the extra color bits.


My mistake, I couldn't remember the number of pins on the GPIO used for it and didn't reference it. Still it's more color depth than any current console core is going to take advantage of. I don't think it's going to make a visible difference for the average user.

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Re: Original analog video without I/O board? Possible!

Postby Sorgelig » Fri Dec 13, 2019 12:03 pm

Amiga, ao486, Linux apps - 24bits.
Analog audio from I/O board due to simple DAC exhibits loud boom sounds when core is loaded. Audio from converter has no such problem.

Key point is not because direct video provides better video and audio (which is true actually), but it's NOT worse than VGA output from I/O board. Later i expect VGA output from I/O will become optional and will be replaced by secondary SDRAM for more complex cores.

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Re: Original analog video without I/O board? Possible!

Postby MottZilla » Sat Dec 14, 2019 2:39 am

Sorgelig wrote:Amiga, ao486, Linux apps - 24bits.
Analog audio from I/O board due to simple DAC exhibits loud boom sounds when core is loaded. Audio from converter has no such problem.

Key point is not because direct video provides better video and audio (which is true actually), but it's NOT worse than VGA output from I/O board. Later i expect VGA output from I/O will become optional and will be replaced by secondary SDRAM for more complex cores.


I'm guessing it would help for a system with more memory buses?

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Re: Original analog video without I/O board? Possible!

Postby Stremon » Sat Dec 14, 2019 8:56 am

MottZilla wrote:
Stremon wrote:Is anyone else having trouble displaying the main menu with direct video (15kHz RGBs)?
It's weird because all cores that support direct video work perfectly, with on screen menu and all, only the main menu doesn't work.
It seems my PVM can't get a proper sync to work with, I can only see some white line shaking on screen, but no coherent image.
I got one of those tailed HDMI to VGA adapter with audio out, but I couldn't check the chipset since I don't know how to open it without breaking it.
I use a VGA switch to change between the IO VGA and the adapter, but it's really annoying to not be able to use only one.

Also, I understood direct video should have better colors than the IO board VGA, but knowing the limited color space of most old gaming hardware, is there any core that is actually getting a true benefits from it?


Did you make sure both your main MiSTer file and Menu.rbf files are completely up to date? I used Direct Video before I had my I/O Board and the menu displayed fine. If you have the I/O board I don't see any reason to use Direct Video since compatibility is less than from the I/O board.

The I/O board RGB output has 5 bits per channel for 15-bit color I believe. That's enough for around 32,768 colors. Some system examples:

SNES 15-Bit RGB
NeoGeo 15-Bit RGB
Gameboy Color 15-Bit RGB
Master System 6-Bit RGB
Genesis 9-Bit RGB
Game Gear 12-Bit RGB
32X 15-Bit RGB
TurboGrafx 15-Bit RGB

The Playstation is capable of outputting 24-Bit "True Color" RGB but this is not used in gameplay, I think it's only for FMV or possibly still frame artwork. Otherwise Playstation is again 15-Bit RGB.

I'm not as familiar with the computer cores and if any of them are capable of beyond 15-Bit RGB.


Thanks for the explanation!
Yes everything is up to date, I even tried older version or another microSD card to be sure.
I don't see any reason either, but still it doesn't work.
Are you using RGBs too?
I believe it's a problem between the composite sync option and the menu core.

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Re: Original analog video without I/O board? Possible!

Postby MottZilla » Sat Dec 14, 2019 9:12 am

Yes, I use RGBs or RGB with Composite Sync. I also am using a Sony PVM Monitor. I don't use Direct Video currently but when I did there were no issues.

So to be clear only the Menu where you select the core is not syncing but if you blindly select a core it does display correctly? You could work around this by after blindly selecting a core you could use the menu in the core to select another core.

It is very strange for the cores to display fine through direct video but not the main menu. Maybe there is something funny going on with your INI file?

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Re: Original analog video without I/O board? Possible!

Postby Stremon » Sat Dec 14, 2019 9:25 am

MottZilla wrote:Yes, I use RGBs or RGB with Composite Sync. I also am using a Sony PVM Monitor. I don't use Direct Video currently but when I did there were no issues.

So to be clear only the Menu where you select the core is not syncing but if you blindly select a core it does display correctly? You could work around this by after blindly selecting a core you could use the menu in the core to select another core.

It is very strange for the cores to display fine through direct video but not the main menu. Maybe there is something funny going on with your INI file?

Yes, that's pretty much what's happening.
I also tried a brand new ini file too, to be sure it's not wrong.

The way I'm using it so far is having a small VGA switch, to switch between the IO VGA for menu and the adapter for the cores.
It works but it's not really convenient.

It's good to know it works for you tho, meaning it might come from my adapter. I will try buying a different one to test.
I wonder what's the best model to buy? It's hard to know since there are many different ones.

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Re: Original analog video without I/O board? Possible!

Postby witchmaster » Sat Dec 14, 2019 10:06 am

Stremon wrote:
MottZilla wrote:It's good to know it works for you tho, meaning it might come from my adapter. I will try buying a different one to test.
I wonder what's the best model to buy? It's hard to know since there are many different ones.

I had problems with several cores with my previoius hdmi to vga converter. I bought a UGreen one and it works perfectly. https://www.ebay.com/itm/UGREEN-HDMI-Ma ... 2629726481

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Re: Original analog video without I/O board? Possible!

Postby Stremon » Sat Dec 14, 2019 3:34 pm

witchmaster wrote:
Stremon wrote:
MottZilla wrote:It's good to know it works for you tho, meaning it might come from my adapter. I will try buying a different one to test.
I wonder what's the best model to buy? It's hard to know since there are many different ones.

I had problems with several cores with my previoius hdmi to vga converter. I bought a UGreen one and it works perfectly. https://www.ebay.com/itm/UGREEN-HDMI-Ma ... 2629726481

Thanks, I will try it :wink:

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Re: Original analog video without I/O board? Possible!

Postby sqwirral » Tue Dec 17, 2019 3:35 am

ShyBry wrote:
Lightwave wrote:
I’m thinking of getting this Rankie pigtail adapter to test, has anyone had any success with it?

https://www.amazon.ca/gp/product/B00ZMV7RL2/


I have this one. It works with direct_video=1. Different board layout inside than some of the pictures in this thread though.


I just got the same one, doesn't work for me. I get audio through the adapter but nothing through the TV at all. Maybe it's the vga-to-scart cable at fault, no idea how to tell which ones work and which don't.

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Re: Original analog video without I/O board? Possible!

Postby Sorgelig » Tue Dec 17, 2019 4:20 am

sqwirral wrote:I just got the same one, doesn't work for me. I get audio through the adapter but nothing through the TV at all. Maybe it's the vga-to-scart cable at fault, no idea how to tell which ones work and which don't.

if you get the audio then most likely adapter works. Most likely your TV doesn't support the frequency.

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Re: Original analog video without I/O board? Possible!

Postby sqwirral » Tue Dec 17, 2019 4:45 am

Hmm ok but I tried 3 tv's so far and all of them work with real 60hz consoles :/
I never get any luck with hooking things up to CRT - jamma, pi, pc, nothing has ever worked. Oh well I'll wait to get an I/O board.

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Re: Original analog video without I/O board? Possible!

Postby warham » Tue Dec 17, 2019 11:29 am

sqwirral wrote:Hmm ok but I tried 3 tv's so far and all of them work with real 60hz consoles :/
I never get any luck with hooking things up to CRT - jamma, pi, pc, nothing has ever worked. Oh well I'll wait to get an I/O board.


you can use the hdmi to vga adapter without running in direct video mode.

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Re: Original analog video without I/O board? Possible!

Postby sqwirral » Tue Dec 17, 2019 12:21 pm

warham wrote:
sqwirral wrote:Hmm ok but I tried 3 tv's so far and all of them work with real 60hz consoles :/
I never get any luck with hooking things up to CRT - jamma, pi, pc, nothing has ever worked. Oh well I'll wait to get an I/O board.


you can use the hdmi to vga adapter without running in direct video mode.

Yes, I tested the adapter going straight into VGA input on my LCD TV without direct video, and it works fine. The I enabled direct video just to see what happened and the TV says it can't display that freq, so it looks like the adapter is fine and the TV just doesn't do 240p over the vga input which is to be expected.

My issue seems to be the vga-to-scart cable is actually a scart-to-vga cable, the cheap ones off ebay, and from reading here https://github.com/mist-devel/mist-boar ... ScartCable my cable won't work but I should be able to open it up and move a few wires around and get more success :D I'll try this later. Thanks!

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Re: Original analog video without I/O board? Possible!

Postby sqwirral » Wed Dec 18, 2019 3:59 am

I got it working!

Image

It looks amazing, maybe even sharper than a real MD. Can't wait to see how much better the SNES core looks compared to the blurry output of the real thing.

Thanks sorgelig :cheers:

Just a recap for how I got it going:
--purchased Rankie HDMI to VGA Adapter with 3.5mm Audio Port for £6
--cut the end off a spare VGA monitor cable and stripped the wires, and directly connected them to a scart connector using this diagram from the MIST github no resistors needed
--added direct_video=1 to MiSTer ini, and set composite_sync=1 as well

I've ordered a proper cable from amigastore too, it's a bit expensive at £13.99 + £2.99 shipping but the one I made myself is likely to fall apart if an ant coughs within 500 yards, so https://amigakit.amiga.store/product_in ... cts_id=919

Now I wonder do I really need the I/O board? Can the buttons on it be accessed with keyboard shortcuts? (Not sure what they do aside from the Menu one)
Edit: Yes, still need I/O board, lots of cores not working with direct_video yet

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Re: Original analog video without I/O board? Possible!

Postby Sorgelig » Wed Dec 18, 2019 1:38 pm

I/O buttons are doubled by keyboard shortcuts.
Cores are going to be updated to support direct video.


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