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RGB said:
Actually it is safe to connect HAS (V3/V3.1 and fixed V2/V2.1) set to TTL. The CMOS CSync signal goes through in series 470R resistor and along with the 75R to GND on the FM/OSSC Scart side forms a voltage divider, so the signal will have ~0.688V amplitude. OSSC VGA port doesn't terminate the CSync (it goes directly to 74LVC2G17 for buffering), but it's a +5.5V tolerant input.
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Thanks rtw, I don't have a Framemeister, so I can't speak to that, but the only reason I left the TTL on with my OSSC is that RGB said it was safe! That's pretty much all I have to go on! So far, so good!
 
xtrasmiley said:
Set Atomiswave hi-rez dip switch to on, get 480p passthrough, looks much better but aspect ration is off, cannot correct.
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Set the Atomiswave to VGA/31hz, and set the OSSC to allow 2x scale on 480p, then set the output aspect ratio to 4:3.
Remember if you are using "passthrough" the OSSC cannot control the aspect, but your TV can (because thats whats actually processing the image) change from 16:9 to 4:3 on your TVs menu.
 
jassin000 said:
xtrasmiley said:
Set Atomiswave hi-rez dip switch to on, get 480p passthrough, looks much better but aspect ration is off, cannot correct.
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Set the Atomiswave to VGA/31hz, and set the OSSC to allow 2x scale on 480p, then set the output aspect ratio to 4:3.Remember if you are using "passthrough" the OSSC cannot control the aspect, but your TV can (because thats whats actually processing the image) change from 16:9 to 4:3 on your TVs menu.
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Thanks, but at 2x, I get a black screen.
 
xtrasmiley said:
Thanks, but at 2x, I get a black screen.
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Try it from a fresh "reset" I think some of the pre/post coast settings could be a problem?
I don't have an Atomiswave, but this is how I do it for Naomi/Dreamcast (should be the same, how is H and V sync handled on Atomis when in 31khz mode? are you bypassing the HAS and connecting the Atomis VGA port directly to the OSSC?).
 
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2 September 2018 HAS testing update, in the future I'll update this post vice making a new one:

At this time I have not needed to purchase a SCART cable to use with the OSSC at all. Please try my settings before spending an extra $20-25 on something you my not need. A small caveat is that you will not have a LPF in this scenario, resulting in very light image distortion most visible on solid backgrounds. See my note below about this. I will retest when I get my SCART cable.

I am using HAS 3.1, OSSC 1.6 FW .81, 8pin min DIN cable with the 8pin mini DIN to HD15 adapter PCB connect to the OSSC, with 3.5 audio cable for sound.

IMG_0467.jpg
HAS 3.1 right side showing 8pin min DIN cable connection and 3.5mm audio cable. These two cables plug into the OSSC (see below). Note that on the HAS I have the jumper (JP2) 75 Ohm/TLL pulled off (meaning it is in TTL mode) and the Switch 1 (SW1) set to (B) Buffered for CSync.


IMG_0468.jpg
OSSC 1.6 version. Left side when looking from top. HDMI cable out and 3.5mm audio cable into OSSC port "A3 IN" from the HAS.


IMG_0469.jpg
OSSC 1.6 version. Right side when looking from top. 8pin mini DIN to HD15 adapter PCB connect to the OSSC "V3 IN" port. 8pin min DIN cable plugged into it from the HAS. Lower cable is the OSSC power.


On OSSC the default setting for Pre/Post Coast is 1. You may have to set to something higher such as 4 to get a good sync for some games. I was able to get a sync on some games at 1 but I have read that others needed a 4 for the same game, so it could be odd tolerances between boards. Finally you must be in mode AV3: RGBS (the first/default mode is AV3: RGBHV).

Atomiswave : Dolphin Blue, Metal Slug 6 =

HAS=TTL, OSSC=Pre/Post Coast on 1, but had to mess with it initially by setting to 4. Now seems to work starting in 1. Set Atomiswave hi-rez dip switch to off, get 480i passthrough, looks like shit, and you must correct the aspect ratio in your TV settings.

HAS=TTL, OSSC=Pre/Post Coast on 1, but had to mess with it initially by setting to 4. Now seems to work starting in 1. Set Atomiswave hi-rez dip switch to on, get 480p passthrough, looks much better but you must correct the aspect ratio in your TV settings.

Capcom CPS2 : Dungeons & Dragons Tower of Doom (Phoenix ROMs) =

HAS=TTL, OSSC=Pre/Post Coast on 1, 3x mode looks best as it doesn't cut off top or bottom but is 720p and 5x mode is 1080p, however the top and bottom are cut off.

Irem M72 : Dragon Breed =

HAS=TTL, OSSC=Pre/Post Coast 1, 3x mode looks best as it doesn't cut off top or bottom but is 720p and 5x mode is 1080p, however the top and bottom are cut off. Also, bottom layer of this games screen is cut off (score, lives, time layer) at the default settings. To see it you have to adjust the settings under Advance Timing Tweaker. I set Vertical Sync Length to 6, Vertical Backporch Length to 30, and Vertical Active Length to 240. This allows you to see the full bottom line information and graphics, however the top is now cut off a bit. You could cut back on my settings to see the numbers, giving up a little bit of the graphics but gaining back the top line. Your call how you rock this.

Irem M92 : Major Title 2, Ninja Baseball Bat Man =

HAS=TTL, OSSC=Pre/Post Coast on 1, 3x mode looks best as it doesn't cut off top or bottom but is 720p and 5x mode is 1080p, however the top and bottom are cut off.

PGM : Demon Front, Espagaluda, The Gladiator, Oriental Legend, Photo Y2K, Photo Y2K 2 =

HAS=TTL, OSSC=Pre/Post Coast on 1, 3x mode looks best as it doesn't cut off top or bottom but is 720p and 5x mode is 1080p, however the top and bottom are cut off.

Taito F3 : Elevator Action Returns =

HAS=TTL, OSSC=Pre/Post Coast on 4, 3x mode looks best as it doesn't cut off top or bottom but is 720p and 5x mode is 1080p, however the top and bottom are cut off.

Sega STV : Radiant Silvergun =

HAS=TTL, OSSC=Pre/Post Coast on 4, 3x mode looks best as it doesn't cut off top or bottom but is 720p and 5x mode is 1080p, however the top and bottom are cut off.

Sega System 16 : Altered Beast, ESWAT, Golden Axe, Shinobi =

HAS=TTL, OSSC=Pre/Post Coast on 1, 3x mode looks best as it doesn't cut off top or bottom but is 720p and 5x mode is 1080p, however the top and bottom are cut off.

Not having a SCART cable makes it so you can play all PCBs with one cable, and avoid having to change the TTL to 75R, which is hard because the jumper is under the plexi, but there is one issue, see below.

*****Low Pass Filter. The HAS uses a THS7316, which doesn't have a LPF (at the frequency we are using for Arcade Boards), but that is normally good because the OSSC has a built in LPF. What you never want is, more than one LPF, or no LPF, so we should be set right? Yes, except the OSSC VGA input that we are using via the 8pin mini DIN to HD15 adapter doesn't have a LPF, so in essence, our feeds in this set up do NOT have a LPF at all, resulting in a picture that isn't as good as it could be. This is likely the reason I have some of the distortion I listed earlier below. Once I get my SCART cable, I'll post my results.******

The ONLY thing I think I noticed, and it's difficult to spot because you need a solid back ground and there is no way to pause arcade games, is that the images seem to have slight distortion in the solid back grounds. You can Google why LPF are important in old arcade/console image clarity to see some examples. It's not terrible, but I'll post more results when I get my SCART cable.

Anyway, a big thanks to RGB for the HAS, Jassin for his testing before hand that let me jump right into playing, and to James at JNX, who is always helping me get shit working!
 
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I was having some issues with video noise, so I made a new 8-pin mini-din to SCART cable (connecting the HAS to the OSSC)...
Only I didn't connect any audio pins (only Red, Green, Blue, Sync and one ground pin #18) in the SCART hood.

32sDNvJ.png


For Audio I ran a 3.5mm to RCA cable directly from the HAS to my iScan DVDO (reintegration into a single HDMI cable, as this setup uses the 1.5 OSSC without digital audio).
I also made sure I had solid continuity (multimeter) between the outside of the mini-din to the outside of the SCART (aka fully shielded) but without bridging to the ground/pin #18 (not sure if this matters because ground might be bridged internally?).

The resulting image was stunning/sharp AF!
Using the LPF and reverse LPF filter (which I believe was originally designed for SNES noise issues?) my Midway boards have never looked so good. :thumbup:
 
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I don't have anything handy, but I have both of my cables (new and old) so I could get some side/by/side shots.
The problem with video noise is its most noticeable on solid color backgrounds, hard to see unless under the perfect conditions.
 
Smart. I always split audio. No good reason for me to ever bring it in through scart because I use pvms with a set of external speakers with a sub for each monitor. Only reason would be if you happen to have a tv with a scart port and good speakers.
 
PascalP said:
nice work @jassin000, got some before/after pics?
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No before pic, but emulator levels of sharpness going on (aka more shots from my redux HAS->OSSC SCART cable) after. :thumbup:
nYyq1NA.jpg


Haha remember that lame comic offer on the attract screen? :rolleyes:
kcQn0ZK.jpg


Yup I've got the reprints...
78oc4Vm.jpg


If you have a printer capable of dual side printing and saddle stapling, all you need are these files. ^^

MK1 Comic
MK2 Comic

FYI the backside page is upside-down and page mirrored, so it will print/assemble correctly on dual sided machines.
 
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do you succes have so nice pic with OSSC? My HDTV have a very low input lag (14ms) but accept only 480p res.
 
hey @jassin000 a noob question for you, I have been doing some reserach on OSSC and Framemeister. A lot of people refer to "Framemeister" as an upscalar vs line doubler for OSSC. Does this mean that with "Framemeister" the image becomes softer as it is displayed on HDTV ?
 
Max_Power said:
hey @jassin000 a noob question for you, I have been doing some reserach on OSSC and Framemeister. A lot of people refer to "Framemeister" as an upscalar vs line doubler for OSSC. Does this mean that with "Framemeister" the image becomes softer as it is displayed on HDTV ?
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OSSC isn't a line doubler per say, it's a scan converter which is also a line doubler somewhat. A line doubler takes a 240p image and effectively just duplicates them to make a 480p image. This doesn't require any intricate math or anything crazy so it requires almost no buffer and has almost no latency impact. A scan converter is a line doubler but it also is capable of attempting to convert to 720p as that is a direct integer conversion from 480p which mostly doesn't require a buffer either. The timing however isn't normalized so a lot of displays don't like the 720p signal as it is not 60hz.

Framemeister or XRGB-Mini is an upscaler where it takes a 240p, 480i or 480p input and can use integrated ics to do a smoother conversion to hd resolutions as 1080p doesn't have a common denominator like 480/720p. It's also much, much easier to use in comparison to OSSC however there are a ton of profiles made now for OSSC which isn't as big of an issue now.
 
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