OSSC Pro

[SL72]

Is there an expected release date for the case for extra AV out board?
Thanks

[Licentious Howler]

I figured I'd follow up on my Master System game sync issue...
I hooked up a different Genesis console, and I've been testing it for quite some time, the sync has been perfectly stable so far, so I guess it was something inherently wrong with the console.
Pretty bizarre it only happens in Master System mode, heh.
Maybe I should check if the voltage regulators are behaving? I have no idea how to intelligently diagnose it and would be shooting in the dark tbh lol.
(unfortunately this alternate "stable" console is a Model 1 VA2 and the composite looks awful lol)

[marqs]

Is there an expected release date for the case for extra AV out board?
Thanks

There are some developments in that direction, but ETA yet.

I figured I'd follow up on my Master System game sync issue...
I hooked up a different Genesis console, and I've been testing it for quite some time, the sync has been perfectly stable so far, so I guess it was something inherently wrong with the console.
Pretty bizarre it only happens in Master System mode, heh.
Maybe I should check if the voltage regulators are behaving? I have no idea how to intelligently diagnose it and would be shooting in the dark tbh lol.
(unfortunately this alternate "stable" console is a Model 1 VA2 and the composite looks awful lol)

The ADV7280 decoder chip on the expansion card does not expose many sync related controls, but its sync processing is supposed to be robust. You can try if the FPGA-based sync frontend has the same issue by connecting composite to Y-input of AV2. Not really a solution as no color decoding is done (B/W picture), but at least you get another hint if there is something wrong on the console.

[Licentious Howler]

Thank you for that tip! I'll definitely give it a try for science.
So actually the VA2 Genesis is occasionally making the expansion board detect different sync randomly as well, it just took a really long time for the behavior to trigger this time (very intermittent problem!).
Again, so far both consoles have only ever done it in SMS mode and with cvbs, pretty weird.
For my personal use, I think simply disabling framelock and turning off the OSD is an acceptable compromise. Might look a bit weird in capture with the picture seldom shifting up and down, but it's workable.

[GameGuru]

Hi all, I just bought my pro and I'm loving it! Thank you everyone who's made it so great. I love the way alternating scanlines looks with 480i in the adaptive mode, but with the scaler i miss out on the alternating scanlines in 480i. Is this something that could be added in a future FW update or is it not possible? Also is a 240p optimum mode available for PS2? I'm playing King of Fighters 2001 and it can display in 240p, but the generic timings are a bit squashed horizontally in LM mode. Thanks.

[Zacabeb]

Hi all, I just bought my pro and I'm loving it! Thank you everyone who's made it so great. I love the way alternating scanlines looks with 480i in the adaptive mode, but with the scaler i miss out on the alternating scanlines in 480i. Is this something that could be added in a future FW update or is it not possible? Also is a 240p optimum mode available for PS2? I'm playing King of Fighters 2001 and it can display in 240p, but the generic timings are a bit squashed horizontally in LM mode. Thanks.

What I've done for the PS2 is tweak the PSX optimized modes to match the PS2 dot clock and use those. The PS2 uses a 54 MHz dot clock (108 MHz in progressive mode,) so the target sample rate is 3,432 samples per line for 60 Hz modes and 3,456 samples per line for 50 Hz modes. Divided by the pixel multiplication factor for each optimized mode gives the following sample rate settings:

60 Hz
256 col: 343.20 samples
320 col: 429.00 samples
384 col: 490.30 samples (horizontal active area needs to be set to either 368px or 384px depending on the game)
512 col: 686.40 samples
640 col: 858.00 samples

50 Hz
256 col: 345.60 samples
320 col: 432.00 samples
384 col: 493.70 samples (horizontal active area needs to be set to either 368px or 384px depending on the game)
512 col: 691.20 samples
640 col: 864.00 samples

The horizontal position of course needs tweaking to align the picture with the new sample rate. I find it easiest to do by first changing the border color in the post processing options to white with a brightness of 1 or 2 so that it shows where the edges are and then center the picture. Then I just switch the border color back to black or set its brightness to 0.

[FlyingFinn]

I experimented today 120hz mode with black insertion (60hz x2). Motion adaptive scaler.

It did seem to work, but now the picture (4:3 area from ps2) seem to flicker constantly in both of my HDMI sources and displayport when connected to computer. Monitor is LG 27” 1440p model.

I was not aware that you could cause some (permanent?) damage to monitor by using 2x hz mode! I tried to reset the monitor settings but it did not help. Now I plugged off the monitor for a while but that did not help either.

EDIT: Seems flicker is getting smaller/away. Strange.

[fernan1234]

EDIT: Seems flicker is getting smaller/away. Strange.

Is this an IPS LCD monitor? You should not use any kind of flickering feature on an IPS panel, as it will cause temporary retention. It will clear over time.

[FlyingFinn]

Ok, thanks, good to know. It's LG ultragear 27GL850-B model. Seems it has nano-IPS panel so I will avoid using 2x hz modes in the future then.

I had OSSC previously and I was aware of BoB de-interlace issue but I did not expect this to happen with 120hz mode as it is 1080p anyway.

[GameGuru]

Thank you Zacabeb that's very helpful! I was also wondering should consoles even be sampled at 320px or 640px? From my testing its been inconsistent because of PAR issues. No console as far as I can tell actually uses square pixels when generating the final video signal. Everything I've seen seems to conform to the 10:11 PAR and generally speaking the generic timings work best except for few fringe cases. I'm guessing the OSSC PRO is sampling at 704x480 to maintain the correct 4:3 digital square aspect ratio witch also means pillar boxing on most sources. Analog video is messy

[GK6475]

When will RF-equipped Legacy AV in boards be up for sale? It'd be really nice to have for older systems.

[Licentious Howler]

https://www.youtube.com/playlist?list=P ... v7QGDAm25J

I figure I might share this here if anybody finds these useful, and if anybody wants to suggest improvements to the format besides "edit better" (lol) feel free.
I am thinking about adding fade-ins when it feels appropriate at least because that wouldn't bloat the complexity of these demos much.
(I let a lot of editing mistakes slip by in the Master System one, ugh)

But I am starting to tackle systems with a lot of AV options now which means there's more potential for oversight or error.
(at some point I will opt to exclude some options--like, I don't think there's any value in demonstrating Wii U analog out lol)

[marqs]

Hi all, I just bought my pro and I'm loving it! Thank you everyone who's made it so great. I love the way alternating scanlines looks with 480i in the adaptive mode, but with the scaler i miss out on the alternating scanlines in 480i. Is this something that could be added in a future FW update or is it not possible? Also is a 240p optimum mode available for PS2? I'm playing King of Fighters 2001 and it can display in 240p, but the generic timings are a bit squashed horizontally in LM mode. Thanks.

It is relatively straightforward to add, but it doesn't necessarily end up looking quite the same after deinterlacing and scaling.

When will RF-equipped Legacy AV in boards be up for sale? It'd be really nice to have for older systems.

They are put on sale once the drivers for the tuner/demodulator IC have been integrated and tested. It's not a trivial task since given API is fairly large but documentation is thin. Would appreciate is someone more familiar with these chips could work on / support development of the feature.

[GK6475]

Odd idea: Would it be possible to have a 720i triple-interlacing output for 720p input signals? Basically, it would draw the first field, then a second field, and then a third field, each of which would probably be 20hz for a 60hz signal, similar to how 480i renders each field at 30hz for 60hz. In this way, could it be possible to have a 720-res signal on an SD display?

[Zacabeb]

Odd idea: Would it be possible to have a 720i triple-interlacing output for 720p input signals? Basically, it would draw the first field, then a second field, and then a third field, each of which would probably be 20hz for a 60hz signal, similar to how 480i renders each field at 30hz for 60hz. In this way, could it be possible to have a 720-res signal on an SD display?

It's a neat idea but probably not possible. It would require offsetting the placement of V-syncs to thirds rather than halves of a line and altering the pre- and post-equalizing pulses to make the triple interlacing work robustly and avoid line pairing. Finally, there is probably no way to make the existing video DAC generate that modified sync and the circuitry in some displays may not be happy with the signal. The interlace flicker would likely be too intrusive for comfort as well – and adding filtering to compensate would negate the benefits.

[Licentious Howler]

I will be publishing something informative regarding the OSSC Pro, and I don't want to give inaccurate info...
there's no tate/yoko feature implemented yet, am I correct in saying that?
Or did I possibly miss something in the menus? I definitely looked everywhere that seemed reasonable, I feel.

[GK6475]

Odd idea: Would it be possible to have a 720i triple-interlacing output for 720p input signals? Basically, it would draw the first field, then a second field, and then a third field, each of which would probably be 20hz for a 60hz signal, similar to how 480i renders each field at 30hz for 60hz. In this way, could it be possible to have a 720-res signal on an SD display?

It's a neat idea but probably not possible. It would require offsetting the placement of V-syncs to thirds rather than halves of a line and altering the pre- and post-equalizing pulses to make the triple interlacing work robustly and avoid line pairing. Finally, there is probably no way to make the existing video DAC generate that modified sync and the circuitry in some displays may not be happy with the signal. The interlace flicker would likely be too intrusive for comfort as well – and adding filtering to compensate would negate the benefits.

Yeah, I figured that flickering would probably be an issue with it, but the idea was definitely still worth mentioning. I don't know if anyone else has mentioned anything like it online, maybe I'm the first to come up with it?

[marqs]

I will be publishing something informative regarding the OSSC Pro, and I don't want to give inaccurate info...
there's no tate/yoko feature implemented yet, am I correct in saying that?
Or did I possibly miss something in the menus? I definitely looked everywhere that seemed reasonable, I feel.

That is not implemented yet, but the HW is capable of it (at least for lower source resolutions).

[Licentious Howler]

Thank you for the reply btw marqs.

I figured I might share this in case somebody else is struggling with it and is stumped:
Oddly, when I connect my Dreamcast with my typical VGA box I've been using for years,
The OSSC Pro processes it with some majorly clipped highlights/whites with default settings.
At first I thought it was an HDMI color range issue, but the black levels were actually just about perfect, only the highlights were clipping.
I then figured it was the Video Low Pass Filter, but no MHz setting really helped the situation.

So the way I fixed this was to go into the AV3 Video in options > and reduce all RGB gains uniformly. Reducing the offsets seems like it crushes black details, so I didn't touch them.
I'm eyeballing, but it doesn't seem like it skews the color along the greyscale if you bring them down uniformly. The default value is 324, and I found that 248 was just about perfect for me.

However, much like my odd Master System sync issues earlier in this thread, I do get some sync jitter just commonly enough to be a problem, so at least on my DC with my equipment, it's definitely a good idea to play in Scaler mode, and disable Framelock, otherwise the picture can randomly cut out.

Hopefully your Dreamcasts play nicer than mine!

[marqs]

So the way I fixed this was to go into the AV3 Video in options > and reduce all RGB gains uniformly. Reducing the offsets seems like it crushes black details, so I didn't touch them.
I'm eyeballing, but it doesn't seem like it skews the color along the greyscale if you bring them down uniformly. The default value is 324, and I found that 248 was just about perfect for me.

Sounds like there is something else wrong if such large adjustment is needed. Perhaps you should try clamp position option.

[jaffa225man]

Thank you for the reply btw marqs.

I figured I might share this in case somebody else is struggling with it and is stumped:
Oddly, when I connect my Dreamcast with my typical VGA box I've been using for years,
The OSSC Pro processes it with some majorly clipped highlights/whites with default settings.
At first I thought it was an HDMI color range issue, but the black levels were actually just about perfect, only the highlights were clipping.
I then figured it was the Video Low Pass Filter, but no MHz setting really helped the situation.

So the way I fixed this was to go into the AV3 Video in options > and reduce all RGB gains uniformly. Reducing the offsets seems like it crushes black details, so I didn't touch them.
I'm eyeballing, but it doesn't seem like it skews the color along the greyscale if you bring them down uniformly. The default value is 324, and I found that 248 was just about perfect for me.

However, much like my odd Master System sync issues earlier in this thread, I do get some sync jitter just commonly enough to be a problem, so at least on my DC with my equipment, it's definitely a good idea to play in Scaler mode, and disable Framelock, otherwise the picture can randomly cut out.

Hopefully your Dreamcasts play nicer than mine!

With my Dreamcast's VGA connection I didn't notice color issues, but sync was a problem. I removed a lot of old flux from my VGA box's PCB when I saw it massively slathered on, thinking of how I'd fixed a NES joystick by removing it, but it didn't change my sync issue. Although turning off framelock works to keep the video signal on sync changes, it still cuts the HDMI-bundled audio out for about a second. Analog audio doesn't cut out on a sync change when using the AV3 audio jack set to AV1 analog audio out, but it doesn't work for this use since the Dreamcast VGA box is on AV3 and needs it for AV3 audio input. So, I played with OSSC input settings until sync seemed better, mainly noticing that increasing "Analog sync Vth" seemed to help, but later it turned out that sync seemed to have less dropouts the longer my Dreamcast (or VGA converter box) was running.

I suspect Marqs is correct and using settings he suggests will fix it, but without further attempts or research, I bought an interlaced/progressive switchable RetroGamingCables Dreamcast SCART cable, which worked for me. In progressive mode it sends the VGA signal (well, except for combining the H+V sync obviously, but it's 31KHz/480p anyway). I have stable sync with it, so either it's cleaning up my Dreamcast's messy signal or my VGA box was my sync problem's cause.

I hope you can solve it without spending the money I did.

[jaffa225man]

With the v0.77 firmware release, I want to point out how great some of the improvements are:

new features added for HDMI frontend
** EDID presets and custom EDID option
** pixel decimation by FPGA (previously RX de-repetition)
new features added for SDP frontend
** audio source selection
** CTI options
1080p line drop modes added
signal info display option added into menu

The EDID presets and custom option make it so much easier because now I don't have to edit the micro-SD card, when I want to make changes to the EDID. Also, the custom EDID files all go into their own directory (edid) on the root of the card, making it much easier to organize them. I still will have to shorten my cutom EDID filenames since they're indistinguishable in the menu, but that's no problem.

The signal info display in the menu works even with my OSD status display set to "off", which I prefer due to unwelcome sync changes making it sometimes display too often. The remote's top-left info button doesn't display with the OSD status display off, so I have had to switch it on occasionally, but this is such a convenient alternative method to see the current I/O settings (and this way without them disappearing after the OSD status display's timeout).

I am quite glad that selecting the audio source is possible, as it has saved me from running long cables at times.

I haven't tried the 1080p line drop modes yet, but it's sure to help with my projector that doesn't scale 1080p down properly (I see just the rightmost area of a 1080p picture, whereas 1080i is detected by name and displays everything fine).

[shmupsrocks]

Can the OSSC Pro be used as a DAC for HDMI in and VGA or S-Video out?

[Amsteffydam]

Can the OSSC Pro be used as a DAC for HDMI in and VGA or S-Video out?

The AV out expansion module allows for this. I have a Gamecube (GC-Video via Pluto HDMI), Wii (hdmi-ave), Wii-U, and Switch all plugged into the OSSC Pro via an HDMI switch. Then output to a CRT TV.

They all look fantastic on the CRT.

[shmupsrocks]

Are many people using it that way? Has anyone compared the output quality to the MiSTer analog I/O boards or the better standalone DACs?

[leonk]

I recently purchased an OSSC Pro, and the last OSSC AV out add-on from VGP. I was wondering if a 3D case for the AV out add-on is available?

I noticed that Stone Age Gamer sells the AV out add-on with a 3D case (where I purchased the OSSC Pro) but this add-on is sold out and why I purchased the add-on from VGP.

[Amsteffydam]

Are many people using it that way? Has anyone compared the output quality to the MiSTer analog I/O boards or the better standalone DACs?

I'm not sure what makes the standalone DACs better. Are they considered "better"?
But it's just barely cleaner to my eyes. I have used analog IO board with component output to my CRT. And I now use direct HDMI to the OSSC Pro, output via the AV out expansion using component to the same CRT.

I prefer the latter.

[shmupsrocks]

I was referring to the fact that some DACs are "better" than others. In your comparison were you using one of the newer or older analog IO boards?

[bobrocks95]

I recently purchased an OSSC Pro, and the last OSSC AV out add-on from VGP. I was wondering if a 3D case for the AV out add-on is available?

I noticed that Stone Age Gamer sells the AV out add-on with a 3D case (where I purchased the OSSC Pro) but this add-on is sold out and why I purchased the add-on from VGP.

Saw a tweet from Matt the other day that indicated cases were available for it. Take another look if you haven't already.

[kitty666cats]

RE: shmupsrocks’ question

The analog out board uses an ADV7125 which is a very good DAC chip. The RetroTink Ultimate used it & the new MiSTer 24bit analog boards use it.

I’ve never seen any commercial HDMI to VGAs that use it - it’s extremely color-accurate, though. There’s also the ADV7123 chip which is 30bit instead of 24bit, but that’s pretty redundant for retro games. It’s cheaper, AFAIK, so I don’t see any reason *not* to use it, unless it’s not as easy to deal with