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29

VGA was introduced in 1987 with IBM's PS/2 line. NEC and VESA developed SuperVGA in 1988, but at the time it used the old and slow 8/16-bit ISA bus. Improving video performance was a top priority at NEC to help sell its high-end displays as well as its own PC systems. By 1991, video performance had become a real bottleneck in most PC systems. (316) ...


28

VGA's 640x480 mode was the first to offer square pixels and an exception among all VGA modes available (320x200, 640x200, 640x350 and 720x400 for Text). Square pixels weren't the standard back then. Adding video modes in later (Super) VGA was kind of a marketing game to offer higher numbers to outpace competition. First it was Colour, like offering 640x480 ...


21

In the UK in the 1980s and the early 1990s, no video input at all was common. Early video recorders and set top boxes (for the new digital channels) would use RF out. You would disconnect the aerial from the TV, connect it to the VCR or STB, and connect the VCR or STB to the TV with another aerial cable. The TV would see it as an extra channel. You might ...


20

All VGAs support the “official” CGA and EGA modes, so most CGA and EGA games work fine. However, compatibility can only be relied upon at the BIOS level; a VGA can be implemented without strict hardware compatibility with the older standards. This affects some CGA games in particular. There is a CGA test tool available. It was written following this ...


20

The 64 has separate outputs on the video port for luma and chroma which you can adapt to an S-Video output. There are a few caveats, however. The chroma signal is a bit "hot" compared to the S-Video standard. The S-Video spec for the chroma line for NTSC is 626.70mVP-P (75% Color Bars), 835.60mVP-P (100% Color Bars) and for PAL 663.80mVP-P (75% Color Bars)...


19

S-Video relies on colour transformation from RGB to YUV, and then takes the U and V and modulates them using a colour subcarrier. The TV has to undo all these steps in order to get the original RGB signal. If the subcarrier frequency is not in phase with the pixel clock (as will be the case if using different crystals), then moving artifacts will show up in ...


19

Up until ~1980 the only connectors TV sets had were Belling-Lee type antenna in. So most VCR and next to all home computers did use RF modulated output toward the TV set (*1). This included even cable networks. While Type F connectors where used for more sophisticated equipment, households were still fitted with Belling-Lee. Professional equipment of the ...


16

Before SCART, European TVs often had not video input at all or S-Video on 6-pin or 8-pin DIN sockets (not Mini-DIN). Cinch composite was uncommon until VCRs came out. After that the old S-Video connectors died out and it was most common for cheap TV sets to have only an antenna and one composite in, better TV sets had a SCART input very early. Component ...


16

I think that this was part of the larger trend of IBM losing the leadership of the “PC”, especially after the PS/2 and the MCA debacle (although the PS/2 line did introduce many new features which became de facto PC standards). Looking at graphics specifically, after the VGA, IBM developed the 8514/A and then the XGA. For most consumers these had several ...


15

Some laptops have built-in support for inverting the screen in one form or another; Toshiba laptops for instance have a setup menu to configure gray-scale translation and inversion, as well as a pop-up TSR and a command-line tool (VCHAD on VGA systems). If your system doesn’t have anything like this, I think your options are rather limited... As mentioned ...


15

Many PC pinball games use Mode X, notably Pinball Fantasies, Pinball Illusions and Epic Pinball. Nerdly Pleasures also has a comprehensive post on games using “unofficial” resolutions, which includes a number of other games which support 320×240: Quake, Earthworm Jim, The Lost Vikings, Norse by Norse West, and Scorched Earth. On Moby Games, such games are ...


13

Preface: The question sounds as if you're missing a basic understanding of interfacing and communication between different chips/systems. At the core it can't be answered without a whole course in digital electronics 101. So I can only try to give some hints to understand the various concepts presented. I've come across a couple of projects that manage to ...


12

1280x1024@24-bit fits in 4 MiB. Why wouldn't you take extra screen space? Keep in mind that games didn't usually run in 1280x1024 at the time. Back before LCDs became the dominating screen technology, you didn't care about the "native resolution" of the display - you didn't get the ugly "one pixel is stretched over two physical pixels, its neighbour only ...


11

The Electron outputs an analogue interlaced 625-line image, with a line rate of 15.625Khz. HDMI is a digital input, so cannot comprehend the Electron's analogue output. VGA is analogue but many monitors expect a line rate of 31 kHz. It's not impossible that your screen would be okay with 15.625Khz though, as that's the PAL standard, so you could at least ...


11

[I]s there ever a circumstance where Mode 13h is a better choice for fast scrolling DOS games over Mode X? Sure, to start with, any single pixel operation on in Mode X is slower than for Mode 13, as the desired plane needs to be set first (*1) Next, the latch-trick (*2) can only move horizontal by 4 pixels at once. So any horizontal scroller will be ...


10

It cost me something like $50 all up to connect my Electron to the TV using an RGB to SCART cable (this one from eBay) and an RGB to HDMI converter like the one pictured below: You can get this model from a bunch of different eBay sellers, under various different brand names, but they're all the same. I've tested it out with MODE 0 - MODE 6, and it seems ...


10

A direct connection is not going to work - The Gameboy's pixel clock is much too low to drive a VGA screen: GameBoy VGA Pixel clock 4 MHz 25 MHz V-Sync 60 Hz 70 Hz H-Sync 9 kHz 31 kHz So, in a nutshell, this will not work without a significant investment into capturing the GBA ...


9

The other answers are good, but one specific area where VGA cards are generally incompatible with CGA is with respect to CGA's Composite mode. In the video "CGA Graphics - Not as bad as you thought!", The 8-Bit Guy demonstrates the CGA Composite mode and explains that, after about 1987 or so, new software written specifically for CGA Composite Mode became ...


9

Black-and-white hi-res from the 1040 STE on a VGA monitor should work with a direct connection and no tricky electronics at all (just the adapter cable) Atari VGA GND 13----X---- GND ---------4 GND Sense 4----+ +--------------2 green ...


9

Your problem is mostly going to be rep movsb changing that to use rep movsw should help. If the VGA card is on a 8MHz (or 6MHz) original AT bus then the timings work like this: 3 cycles to read or write a byte 19,200 bytes being moved. 345,600 bus cycles per copy 8,000,000 / 345,600 is 23.14 copies per second. 6,000,000 / 345,600 is 17.36 copies per second. ...


9

In analog TV, there was such thing as interlace. Roughly speaking, it kind of increased vertical resolution by putting scanlines of one "halfframe" (the one that lasts 20ms or goes 50 times per second, or, alternatively, 16.6ms and 60 Hz) between the scanlines of previous halfframe (saying scanlines I mean lines lit by electron beam on CRT). As the ...


8

The problem you have is that most home computers of that era output TV standard signals which VGA is not. As you've mentioned there needs to be some conversion from one standard to the other. A popular solution that I happen to use is the Gonbes GBS-8200/GBS-8220 boards. They aren't perfect and some people hate them but they are reasonably cheap and I think ...


8

The 5162, more commonly known as the IBM PC XT/286, uses a 16-bit expansion bus. Any 8-bit “ISA” VGA card should work fine (but they are rare), and most 16-bit VGA cards should work too... Ironically, the 8-bit Hercules VGA card is known to cause issues. Some 16-bit cards designed for the PC AT won’t fit in the XT/286’s case and therefore can’t be used ...


8

For tile-based scrolling games of the "platformer" genre, it was certainly an advantage to use ModeX. This is especially true if you wanted to support slower 80286 or 80386SX CPUs with the early 8-bit VGA cards and which lacked VRAM. Here was a "triple whammy" of slow(ish) CPU, limited bus bandwidth, and limitations on shared access to the display DRAM. I ...


8

Quoting Wikipedia, it seems to be at least two factors: The availability of inexpensive LCD monitors has made the 5:4 aspect ratio resolution of 1280 × 1024 more popular for desktop usage during the first decade of the 21st century. (from here) The 1280 × 1024 resolution became popular because at 24 bit/px color depth it fit well into 4 megabytes of ...


8

I have this monitor, which I think is a Commodore 64 monitor. Not really. And especially not for the C64. The screen was manufactured in Taiwan (*1) for/by Philips. It was widely sold as a monochrome screen to many countries. What is true is, that Commodore OEMed it ca. 1985 as 1901(*2) or later 75BM13 (*3) for/with the PC10/20/... series (*4) of IBM ...


7

Some Matrox cards output composite and S-Video using the HD15 port; for example, the G450 PCI (see the TV output chapter in its manual). The adapter cable was optional though and isn’t commonly included with the graphics adapter.


7

You have three problems to overcome: Separate sync from composite video or CSYNC into H and V to get an RGBHV output. Upscale/scan double from 15 kHz to the 31 kHz that most VGA monitors accept. Separate out the audio. The $89 Ambery 15Khz RGB CGA to VGA RGBHV Converter Scaler is a device that appears to do the first two, but I have no experience with it. ...


7

You can invert the screen on a monochrome Omnibook by holding the Fn key and pressing either of the contrast up/down buttons next to the screen.


7

The Veronica uses an 8-bit memory mapped port to send commands from 6502 CPU to the AVR that generates VGA output. Commands can only be sent during the blanking periods and the port ca be read by the 6502 CPU to find out when that is. The ZC160 uses a second Z80 in combination with custom programmed GALs to generate the VGA output. A comment says that it ...


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