Datapath E1 (not E1S) issues with detecting Genesis Model 1?

[kitty666cats]

Hey guys! A buddy of mine is going through absolute hell trying to capture his Genesis Model 1 on his Datapath E1 (NOT E1S, just E1). He connects via the output of his PVM, and is using a switchable in/out RCA RGBS + L/R audio SCART cable into a SCART2DVI to connect to the Datapath.

He's had zero issues connecting this way via his Wii, but his Genesis 1 continues to be finicky and the card will not detect the signal! He is using a RetroGamingCables csync 'Pack-a-punch' cable, specifically,

Anybody else ran into this issue before? He's trying to capture in native resolution, no up-scaling device in between the SCART2DVI and capture card.

[NewSchoolBoxer]

This is a good thread to read through:

viewtopic.php?f=6&t=61203

User FBX captures Genesis 1 on E1 by passing through OSSC and gives OSSC setting near the bottom of the page. Implies can capture through Framemeister as well. States Genesis has very wonky CSYNC and these two upscalers have sync correction options, as do some Extron models. So I think that's the whole problem versus going past the 430 MB/s data rate cap. Wouldn't hurt to try the Sync Strike or any other sync product if on-hand.

I realize your buddy would want to avoid an upscaler that isn't needed for the PVM. Can try reducing the number of connections to the E1 card, including avoiding going into the PVM. The card also accepts YPbPr where maybe the Sync on Green is compatible as is. This would encode to YUV: 4:2:2, which is still better than YouTube 4:2:0.

One more idea that is advanced:
I don't know if E1 takes TTL level (4-5Vp-p) CSYNC but I don't see why it wouldn't. I assume the sync line has both a 470 ohm resistor and 220 µF capacitor to go from TTL to 75 ohm 0.3-1 Vp-p. Remove both the resistor and capacitor from the cable (need soldering skills and will damage the cable) and send the TTL sync unfiltered. The resistor and capacitor create an RC time constant of 103 ms (470*220µ) aka Elmore Delay. That is many times higher than the 0.120 µs sync rising time on NTSC and 0.200 on PAL. I don't like the 470 vs 75 ohm impedance mismatch either.

A console straying to the limits of sync timing that a PVM can accept I don't think should have sync modifications that aren't specifically to correct the timing. I don't follow NES RGB modding closely but they had a juttering issue that applied to the 75 ohm sync attenuated with resistor + capacitor and not TTL the video chip produced.

[NewSchoolBoxer]

Sorry I didn't find this first: viewtopic.php?f=6&t=66834

You can't feed TV level sync into the datapath, it needs TTL level. Normally a sync stripper would fix this but I have a feeling your stripper probably steps down the new signal back to TV level.

So my solution will work, barring Genesis wonky timings independent of the voltage level. Better to use a device I mentioned or sync separator chip to bring back up to TTL if you want to avoid soldering or buying a new cable that outputs TTL.

[kitty666cats]

My buddy actually ended up figuring this out... it was some matter of cabling, I believe?

@NewSchoolBoxer - the SCART2DVI accomplishes what the Sync Strike can do, with the added bonus of being able to switch off the LM1881 if needed (plus has a LPF you can switch on and off!)

Since this issue is alleviated, mods can close this thread if they want

[NewSchoolBoxer]

SCART2DVI, you say? Why don't I see what that does?

This device is powered by USB, passes through audio and has toggle switches for both the LPF and sync stripper.
I wanted to post a quick update on the SCART2DVI, Comp2DVI and VGA2DVI Datapath Vision passthrough boards from the video capture section: https://www.retrorgb.com/videocapture.html

Oh. So it's supposed to go into the capture card so wouldn't be attenuating the sync outpu and every sync stripper chip outputs TTL.

That was good of me to overlook. I thought no one responding meant the issue had to be something difficult.

Glad it's up and working! I want to see more RGB video content.

[kitty666cats]

SCART2DVI, you say? Why don't I see what that does?

This device is powered by USB, passes through audio and has toggle switches for both the LPF and sync stripper.
I wanted to post a quick update on the SCART2DVI, Comp2DVI and VGA2DVI Datapath Vision passthrough boards from the video capture section: https://www.retrorgb.com/videocapture.html

Oh. So it's supposed to go into the capture card so wouldn't be attenuating the sync outpu and every sync stripper chip outputs TTL.

That was good of me to overlook. I thought no one responding meant the issue had to be something difficult.

Glad it's up and working! I want to see more RGB video content.

Insurrection Industries removed it from their website since it's niche/wasn't a hot seller. If you messaged them prior to purchase, they would gladly attentuate video or audio if asked. I contacted them recently when I saw it was no longer in their website, and suggested perhaps a new version with a VGA-style connector on the end (for GBS Control / Extron interfaces / etc).

The unit was $35, and their website just happens to offer free shipping for orders $35 and over. Was a much, much nicer deal for NTSC folks compared to importing a Sync Strike. Also a nice alternative to those female SCART to BNC cables with built-in sync strippers, provided you had a couple spare cables already sitting around (3.5mm to 2RCA, micro USB cable for power, DVI-I to VGA dongle [for some reason I always end up having OODLES of these sitting around], plus a VGA to BNC cable )

If enough people expressed interest, they'd def make more. I think the original design may be the work of Bob from RetroRGB...? Shmups user @retrorgb
Not certain though. Voultar designed a similar PCB that also has an included SCART ~OUTPUT~ designed for streamers, etc. Called the design "Double Penetration" OH, so naughty, lol @ SEX STUFF

[NewSchoolBoxer]

$35 with free shipping is amazing. I need to clean Composite Video as Sync into CSYNC off my PS2 to feed into E1S but it's hard to justify a $49 Sync Strike that ships from Germany. More if I need the PSU. RetroRGB does show how to solder and wire the LM1881 up but I'd need more work to go from JP21 pin out to JP21 or BNC pin in. I can record YPbPr as is.

Nice that Insurrection ships from US for our sake and that's cool they'll solder a resistor at no charge. I can imagine a SCART2DVI being niche. It seems like everyone has PVM or SCART CRT but then I visit my family member who hasn't heard of either and uses a Composite switch to LCD for SNES/GameCube/PS2. Doesn't care about scanlines and can record off emulator. We're just loud because we have all the problems and found a hardcore group to sit around the campfire with.

VGA to BNC breakout cables are so cheap I got one for free. VGA <-> DVI-A adapters are passive and cheap. 4-1 VGA switches for $21 and free shipping from Amazon and Monoprice!

Make Nintendo and Sony Multiout to VGA a thing with BIG WARNING STICKER that it's not compatible with computer monitors. Issue we run into is no one with existing SCART/JP21 setup is going to convert.

[kitty666cats]

$35 with free shipping is amazing. I need to clean Composite Video as Sync into CSYNC off my PS2 to feed into E1S but it's hard to justify a $49 Sync Strike that ships from Germany. More if I need the PSU. RetroRGB does show how to solder and wire the LM1881 up but I'd need more work to go from JP21 pin out to JP21 or BNC pin in. I can record YPbPr as is.

Nice that Insurrection ships from US for our sake and that's cool they'll solder a resistor at no charge. I can imagine a SCART2DVI being niche. It seems like everyone has PVM or SCART CRT but then I visit my family member who hasn't heard of either and uses a Composite switch to LCD for SNES/GameCube/PS2. Doesn't care about scanlines and can record off emulator. We're just loud because we have all the problems and found a hardcore group to sit around the campfire with.

VGA to BNC breakout cables are so cheap I got one for free. VGA <-> DVI-A adapters are passive and cheap. 4-1 VGA switches for $21 and free shipping from Amazon and Monoprice!

Make Nintendo and Sony Multiout to VGA a thing with BIG WARNING STICKER that it's not compatible with computer monitors. Issue we run into is no one with existing SCART/JP21 setup is going to convert.

I got a hunch cables with VGA-style connectors are gonna catch on more and more, hah. I ordered this badboy recently, speaking of which:

https://www.ebay.com/itm/Creator-Profes ... 3775120639

I AM running a SCART switchbox into one of the inputs on this thing via a female SCART to VGA style cable with a LM1881, lol, but I'm probably gonna do a full switch-over away from SCART in the near future, and get a Matrix like the above one with just a teensy few more inputs/make some custom console cables. And sell off a massive load of neato SCART cables, adapters, switches, splitters + even an obscure SCART to 31kHz VGA scaler! All for someone else new to da game to show some love to, or w/e. Heh.