November 29th, 2024

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

The article examines challenges in capturing screenshots from vintage systems, focusing on the Hall SC-VGA-2 video processor and Inogeni VGA2USB3, detailing setup, internal architecture, and successful image captures.

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

The article discusses the challenges and solutions for capturing screenshots from vintage computing systems, particularly focusing on the Hall SC-VGA-2 video processor, Atari ST, and NeXTSTEP. The author highlights the limitations of existing hardware and software in obtaining high-quality screenshots, especially during boot processes where operating system support is lacking. The Inogeni VGA2USB3 is mentioned as a preferred capture device, but it has limitations regarding refresh rates. The Hall SC-VGA-2 is introduced as a versatile video processor that can rescale and resample various input formats, making it suitable for capturing images from older systems. The author details the setup process, including connecting the SC-VGA-2 to different systems and adjusting settings for optimal output. The article also touches on the internal components of the SC-VGA-2, suggesting it operates as a two-CPU system, with one handling user interface tasks and the other managing video processing. The author successfully demonstrates capturing boot and shutdown sequences from NeXTSTEP and discusses the potential for capturing images from the Atari ST. Overall, the piece serves as a technical exploration of vintage computing and the ongoing efforts to document and preserve these systems through improved screenshot techniques.

- The Hall SC-VGA-2 video processor is effective for capturing images from vintage systems.

- The Inogeni VGA2USB3 is a preferred device for high-quality video capture but has refresh rate limitations.

- The article explores the internal workings of the SC-VGA-2, suggesting a dual-CPU architecture.

- Successful image captures from NeXTSTEP and Atari ST systems are demonstrated.

- The challenges of obtaining screenshots during boot processes are highlighted.

Programming Like It's 1977

The article explores programming games on the Atari VCS, a pioneering hardware platform from the 1970s with constraints that inspired creativity. Coding in 6502 assembly language offers a retro experience. The Atari 2600+ release supports old hardware for modern gaming. Learning on the Atari VCS reveals early programmers' challenges and solutions, fostering creativity.

Apple II graphics: More than you wanted to know

The article explores Apple II graphics, emphasizing its historical importance and technical features like pixel-addressable graphics and sixteen colors. It contrasts with competitors and delves into synchronization challenges and hardware details.

Graphics Tricks from Boomers

Arnaud Carré's 4096-byte intro for the Atari STE showcases advanced graphics techniques, including stroboscopic effects and video signal manipulation, aimed at retro computing enthusiasts and graphics programming.

Atari ST Programming: Hatari, STOS and Turbo C

The article reflects on the Atari ST, a 16-bit microcomputer, its programming tools like STOS and Turbo C, and emulators Hatari and STEem, with plans for future coding examples.

My new POWER Indigo 2

The author restored a rare Silicon Graphics POWER Indigo 2 workstation, originally priced at £30,000, successfully booting it with the IRIX 6.2 operating system and plans to explore its capabilities further.

3 comments

By @CursedSilicon - 5 months

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-...

By @johnklos - 5 months

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 :)

By @tom_ - 5 months

I've got a mono->VGA cable for my STe, and it doesn't work with all LCD monitors. I've got a 4:3 1280x1024 display that (after tweaking display settings) resolves it to a pretty clean 1280x800 with a border at the bottom, but I tried it with a couple of displays a friend has and it seemed impossible to get it quite right. The output was very similar to the nasty screenshots shown here: monitor's pixel sampling always slightly out of sync. I wonder if it's the same phenomenon.

I vaguely remember 70 Hz and 72 Hz being VGA standards, so the ST's 71.25 Hz (or whatever it actually was) could be a bit of an oddity.

(The Nextstep output doesn't look that awesome either! Hard to say whether this is the converter or whether it's like that it source thouh.)