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111

When CD-ROM games were first introduced, game developers didn’t take any measures to prevent users from copying them, for two main reasons: CD-ROMs could contain more data than most hard drives at the time; CD writers were rare, and extremely expensive. The Wikipedia page on CD-R gives some idea of the expense involved: in 1990, CD recording systems cost ...


91

Bootable game disks do exist for the IBM PC. Conflict in Vietnam is an example of such a game. As can be seen on page 8 of the manual, the game boots directly without loading DOS first. The main reason it wasn't common was for compatibility. A self booting game has to have its own drivers for all the hardware it wants to support. As PCs quickly diversified ...


84

How does the Sonic & Knuckles cart detect another cartridge? It checks the serial numbers of games; they can be found in the ROM's header. It probably detects all preceding Sonic the Hedgehog games since they all result in specific effects when locked-on. Are the game ROMs merged in some way when connected? It seems both games are simply mapped onto ...


77

They're called paddles because they let you play (electronic) table tennis. :) This article from CREATIVE COMPUTING VIDEO & ARCADE GAMES VOL. 1, NO. 1, 1983 explains. The reason this control is called a "paddle" in the personal computer industry is that it originally got its name from the control which moved the paddies[sic] on the screen in ...


75

well, if you really want those games back, just buy the tape. Then buy a cassette player (they're cheap, you can try to get a high quality one) or find a friend who still has one. Now: Make sure to clean up the player heads with isopropyl alcohool before using it. Rewind the tape Extract it and use 2 pencils on the reels to gently tighten the tape so it's ...


68

Did every programmer of every game implemented all possible various API's that old graphic cards supported? Yes - but it went even deeper than that. Early graphics cards had virtually no callable code associated with them at all, the concept of "drivers" had not quite become a reality yet. There was the concept of a Video BIOS, which were extensions to the ...


66

Interestingly enough, I stumbled in a related article, that hints firstly the (cross)development at Sinclair was made on CP/M machines, (which corroborates the Matthew Smith Manic Miner development in the TRS 80 reference on the OP question), and later on in CP/M emulated under a VAX for (re)using the original binary (cross)toolchain. At Sinclair, a £60,...


65

So, why was this so widespread? Was it simply because it was easier to do than anything else (and, you know, limited hardware of the day), Exactly that. To make a sprite blink, all you've got to do is to set it to be not displayed and then displayed again. Usually by just writing a single register or pointer or setting a flag to skip drawing it. No ...


54

This is quite a wide-ranging question. There are some resources online which help: Jonathan Cauldwell, author of various Spectrum hits, has a How to write games for the Spectrum" guide, which seems to mainly cover modern Speccy development. The Oliver Twins (authors of many Codemasters-published titles back in the day) detail some of their development ...


50

Video game hardware, whether for home consoles or arcade machines, is designed pretty much from scratch. Hardware designers have pretty much free rein on choosing what CPU to use, basing their choice on factors like cost and ease of programming. The Intel 8086, quite frankly, was a poorly designed processor and was never well regarded. While you could ...


50

Your assumptions about timing and interrupts are correct. Actually, it is surprisingly easy to add SID music to games because they tend to follow a basic pattern. Compose the tune in a C64 SID editor. There are many of these. The SID editor generates a SID file, which actually includes both the data and code for playback. This file is easily incorporated as ...


47

We had some software delivered on a CD in which the vendor purposely put a defect on a specific track. If that defect wasn't there, the software could say it wasn't an original CD. Since defects are not copied, even on low level track copies, an exact replica could not be created.


43

TL;DR: In the US Channel 3 was preferred as it was in the midst of the continious 2/3/4 assignment. By lifting or lowering the carrier by 6 Mhz either channel 2 or 4 could be offered as alternative. Another-Dave already answered the basic issue of avoiding collisions. The reason why it was channel 2/3/4 is due historic channel assignment (in the US, *1). ...


40

I'm putting CHIP-8 forward. This system is essentially a virtual machine developed for some reason. There are games written for the CHIP-8. It has a few opcodes, a stack, a couple of timers, and a low resolution bitmapped display, but it's simple enough that the first few emulators fit in a few kilobytes on early 8-bit computers. There are more than a few ...


35

Why tune the TV to a channel at all? Early consumer television sets were built for one purpose: to watch broadcast television. The only input was for an antenna. The idea of using your television set for any other purpose simply wasn't yet conceived, so there were no connectors for any other kind of signal. The first additional uses for household ...


34

In addition to the other answer and comments, a character would often enjoy a brief period of invulnerability after sustaining damage — this period was indicated with the character blinking. The blinking effect here helps suggest an ethereal state where you can’t suffer more physical damage.


33

The first game sold for use on the IBM PC was Microsoft Adventure, which was available on the day the IBM PC was released (it was part of the launch, along with VisiCalc, Easywriter etc.). It was developed by Gordon Letwin (later of OS/2 fame) in 1979, based on the Colossal Cave mainframe game. It didn’t run on DOS though, it was a “booter” — you booted the ...


32

There are two elements: The background The sprites The background is very straightforward: The vanishing point never changes so you have one graphic with a checkerboard in perspective. That graphic takes 2 bits per pixel so that you have the 2 checkerboard colors and the edges of the field color. It just needs to be the width of the screen + 4 tiles (2 ...


32

Back in the '80s, I wrote a couple of games too. A few years ago I have found the old cassettes with those games, but I had no tape deck at all. I bought a "USB walkman" Basetech BT-USB-TAPE-100 on eBay for a few dollars. Then I just plugged this deck to my PC and record my old tapes to uncompressed WAV (at full possible sample speed, 48 kHz, 16 ...


30

The nicest DOS emulator for macOS is Boxer, which is a macOS-specific version of DOSBox. Not only is it free, it's free software (or open source if you prefer); its source code is available and freely modifiable. There is currently no “official” 64-bit build, which means the distributed application won’t work on the latest versions of macOS, but there are 64-...


29

Excess capacity. ROM chips come in standard sizes based on powers of 2 and it is quite unlikely a particular size will be exactly what a game needs. For example, suppose a game displays numbers that are 8 x 8 pixels in size. It will need the digits from 0 to 9, each digit needs 64 bits so a ROM of 640 bits is required. That could be accommodated with a ...


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

The cartridge contains extra RAM. The NES can use tiles in cartridge memory space, but that doesn't necessarily have to be ROM. With suitable RAM and memory mapping the cartridge can create a basic bitmap display out of tiles. The vectors are then rendered to that RAM using the NES CPU in the normal way.


28

Early on, you had to explicitly code your game for each graphics card you wanted to support: Hercules, CGA, Tandy, EGA, VGA. You had to know how to put the card into graphics mode and you had to know the memory layout, palette, and so on. You had to figure out how to avoid flicker and how to prevent tearing. You had to write your own line drawing and fill ...


25

The gameplay can be implemented without any 3D calculations (or very little, depending on your definition of 3D calculations): The checkerboard never rotates, so it can be drawn using affine segments and fills (y = ax + b); the players never get close enough to the edges (on the goal sides) for the vanishing point to be an issue. The checkerboard isn't ...


25

Well there were some PC booter titles (MobyGames lists 249), but most of these were quite early games, even before hard drives, XMS or EMS even existed. These were almost always self contained single floppy games, that could run on the very specific hardware that existed. All they used was BIOS for disk access. Also DOS was not the only operating system, so ...


24

The Amiga hardware supported only bitplane graphics, and you could have as many or as few bitplanes as you desired, up to certain bandwidth and archtectural limits. A neat trick of the Amiga's video hardware is to superimpose two three-bitplane screens and scroll them independently, which is obviously pretty useful for games. I tended to use an eight-colour ...


23

(preface: While Stephen's answer already covers the basic points, I would like to put a different emphasis here - and merge in some private history :)) Short answer: It was the game's size and the need to copy it to a CD again, combined with expensive and unreliable writers. Further, the CD itself was used as a copy protection. While games often got ...


22

The adventure module on PyPI is a faithful, modern re-implementation of the 1977 PDP-10 FORTRAN version of Adventure (aka the “350-point” version), which goes so far as to re-use the exact same advent.dat file: This is a faithful port of the “Adventure” game to Python 3 from the original 1977 FORTRAN code by Crowther and Woods (it is driven by the same ...


21

Ultima V was I think the best known game that behaved differently on a Commodore 128 than it did on the Commodore 64, on the C128 it had music but not on the C64. I believe this was accomplished by separate C64 and C128 versions on the same disk. Apparently some of Andrew Braybrook's games for the C64, like Morpheus and Alleykat, took advantage the ability ...


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