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The Hall SC-VGA-2 Video Processor, the Atari ST and NeXTSTEP

45 points12 hoursoldvcr.blogspot.com
CursedSilicon9 hours ago

I'm surprised they dismissed the OSSC [1] so easily. It's not "just" for game consoles and arcade equipment. It has a VGA port on it for a reason!

Admittedly I haven't used it for anything nearly as "esoteric" as some of the gear Cameron has I'd be surprised if he encountered any issues. Though being open source I'd suspect if he did he could simply fix them himself in the OSSC's firmware if needed!

An OSSC will happily upscale any weird resolution/framerate you feed it to something modern HDMI devices can "understand". I use an "EVGA XR1 Lite" [2] to take the OSSC's HDMI output and feed it in over UVC to my laptop with USB-C. Works flawlessly and is dirt cheap

If Cameron wants a bit more of an "all-in-one" solution, myself and other retro tech youtubers like Tech Tangents, RetroRGB and others use old Datapath RGB E1S cards [3]. This thing is basically just a DVI port glued to an FPGA. It doesn't care about "resolution" or "refresh rate" it just DMA's raw pixel data right into RAM and lets what ever application you point at it decipher it. Personally I think they're pretty awful (comparatively) to the above option. The driver is a binary blob (so it probably won't work on Cameron's POWER machine) and it crashes a lot both under Windows and Linux. Though it seems more agreeable under Windows for changing resolution and other settings via OBS

[1] https://www.retrorgb.com/ossc.html

[2] https://www.evga.com/products/product.aspx?pn=141-U1-CB20-LR

[3] https://www.datapathltd.com/datapath-products/video-capture-...

classichasclass8 hours ago

(author) Hey, thanks. I'm still sceptical about the OSSC for this application. It doesn't seem to downsample from higher refresh rates, which is specifically what I picked up the Hall converter for (at least as far as I could tell from the wiki at https://junkerhq.net/xrgb/index.php?title=OSSC_Pro ). https://stoneagegamer.com/ossc-pro-open-source-scan-converte... just says "Common PC resolutions up to 1600×1200". The cost of a OSSC Pro unit makes me hesitant to try this out. If you're sure it can do it, though, I'll get my pennies together to give it a shot.

snvzz5 hours ago

With the OSSC, you'd have pixel perfect sampling.

Rather than the mess (see wavy pattern on TOS background) that you have now.

I use mine with Amiga (OCS, ECS, AGA), VGA and a Wii.

OSSC Pro is costly, in good part due to cost of FPGA and other components used, but the simpler OSSC is typically under $100.

OSSC Pro is able to buffer full frames, deinterlace and have different input and output timings, whereas OSSC operates with only a couple of lines of video data, thus is less flexible, but sufficient for most uses, with excellent low latency.

classichasclass5 hours ago

I've seen reports of success with the ST, but that's a 640x400 display at most (the lower resolutions run at lower rates anyway, which the OSSC seems to handle well). But what about higher resolutions or refresh rates? The issue with the HP was resampling a 1024x768 70/75Hz signal to 60Hz.

snvzz4 hours ago

The OSSC can sample even 1080p input signals.

If you need wildly different timings for the output, you'll want the Pro, which unfortunately isn't cheap.

As for "will it capture this weird mode?" general question, it will. It does have tremendous sampling flexibility. IMHO the main selling point of the OSSC.

johnklos9 hours ago

Oooh! I wonder if I can find one of those. I'd love a way to see all of the Amiga screenmodes on a single display :)

classichasclass8 hours ago

I don't think it can scandouble - my A4000T with a Picasso RTG card uses the onboard doubler. But if the video mode is at least 60Hz, odds are this thing would probably support it.

snvzz5 hours ago

Look into the OSSC Pro.