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210

I'm the author of the TPUG article. The "BILL GATES SUCKS" message isn't really an Easter egg; that was just a conceit of mine to make the article a bit more interesting and to turn it into a bit of a puzzle. Here's how it works and how it was created: In any given infinite sequence random numbers, it's a mathematical certainty that a given subsequence of ...


90

The term "Disk Operating System", or commonly "DOS", was used in the early days of personal computing to distinguish operating systems that also contained software for supporting disk devices, since not all of them did. The DOS software could access blocks stored on disk, that were organized into files, and there was "filesystem" software included for ...


62

It doesn't imply that it's the disk operating system so much as it implies that it's the disk-operating system. You could boot an Apple II from ROM, enter and run BASIC programs, load programs from cassette, and basically do whatever an Apple II can do, but there was no way to access files on disk. Apple DOS didn't really do any of the features of a modern "...


54

I don't think that's an easter egg. Someone just made an effort to find random seeds that produce the numbers to create the intended words. It would be an easter egg if the seed numbers were in some way related to CBM or Microsoft. A=RND(-A) initializes the (pseudo) random generator with A, generates a random number and stores it in A. The GOSUB20 ...


39

The term DOS pre-dates the personal computer by a looong way: the term DOS/360 was first coined by IBM in 1964 as a new operating system for their System/360 mainframe computers, to replace TOS (tape operating system). IBM commissioned Microsoft (at that time a garage outfit) to write PC-DOS to run on their Personal Computer, which was launched in 1981. ...


37

The way I understand it, ROMs are like virtual games, Not really. ROMs are a piece of hardware storing a bit image. Like a disk, a tape or a punch card. It holds an image of the game's software. and emulators are like virtual game consoles, or handhelds. Basically yes. What I don't understand is how there are ROMs for arcade games, which don't have ...


27

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 ...


27

I'd guess a lot of the systems used for development didn't clean the memory down in between usages. It's also likely that for games "gaps" got left between binary chunks. So if for a hypothetical system redefined characters had to start on a multiple of 256 (0x100) byte boundaries the memory layout might have looked like this: 0x0000 - 0x1789 - Compiled ...


20

The other answers already covered a lot, but there is something else that is important but which hasn't already been addressed in detail: Despite appearances to the contrary, arcade machines are quite frequently not built with unique hardware. For example, the hardware originally designed for Galaga was used for several additional games, including well ...


17

In the personal/home computer space, the usual model was that the machine shipped with built in BASIC and the ability to save and load data from an attached cassette tape. This includes the original IBM PC, which had BASIC in ROM, as well as a specific cassette port that included a relay for controlling the cassette motor. BASIC itself included a MOTOR ...


17

Does "Disk Operating System" imply that there was a "non-disk" Operating System? Yes. A little bit of history The earliest computers did not even have Operating Systems. The earliest computers were mainframes that lacked any form of operating system. Each user had sole use of the machine for a scheduled period of time and would arrive at the computer ...


17

Does fast page mode apply to ROM? No. Why should they? You're missing one step to start with in your chain of thoughts. (Fast) Page Mode is an improvement to the address multiplex protocol dynamic RAM uses. As such it isn't a general improvement, but a relative one, reducing the overhead the address multiplexing implies. Address multiplexing was ...


16

I don't know if this applies in every case, but, on the Commodore PET and by extension C64, an executable program file on disk/tape consisted of a load address (normally $0401 on the PET) and then literally a memory dump of the the region of RAM containing the program. The normal save routine would save all the memory until it got to the end of the BASIC ...


16

I've done this partially with Commodore PET Space Invaders which I used as a test program to debug my Commodore PET emulator. I used a disassembler to convert the program to assembly language and I then went through the code annotating it as I found out what it does. When I understood what a bit of code did, I would look for its entry point (my disassembler ...


15

The page you linked on The Cutting Room Floor offers its own explanation: Sometimes this is to pad out a disc or ROM to fill any empty space, other times it's just funky compiler behavior... "Funky compiler behaviour" is the most likely explanation for the older games. More specifically, as explained in Muzer's comment, it's likely because memory was ...


13

The original Apple II has up to 48K of RAM from $0000 to $BFFF and 10K of ROM between $C000 and $FFFF except for a hole between $D800 and $DFFF. You can get a language card which puts 16K of RAM under the ROM space. The Apple IIe has a full bank of 64K of RAM, just like the Apple II with the language card installed. The 128K models have an additional 64K ...


13

The GBA's memory controller can be configured using WAITCNT, an MMIO port at 0x04000204, to use slow or fast timing when accessing the Game Pak slot. The BIOS boots up in slow mode, in case Nintendo would release games on slow ROM. But Nintendo ended up releasing all games on fast ROM, and when a game starts, it writes a value to WAITCNT to enable fast ...


12

The standard US Apple //e Video ROM was pin compatible with 2732 (4k) EPROMs, but some foreign models (UK, German, French, Italian) used a 2764 (8k) compatible ROM with two character sets. Your clone might be the same or it might be different - the best way is to try to decode the pinout using either a logic probe (while on) or even a multimeter (while off) ...


11

Simple Answer: Unlimited and Many Ofc, every system can only reserve a certain amount of real address space for cartridges, but then there is Bank Switching. Just take the original Atari 2600. Address space for ROM was 4 KiB, and many early games only used 2 KiB ROMs. But already in 1982 Burger Time came in a cartridge with 16 KiB ROM and some sort of bank ...


10

Where could I find a list of all of the microchips released by Intel, including microprocessors, Rams, roms, storage devices. Etc. Oh, that's a simple one: Get the Databooks Intel, like any other manufacturer, has a good history of publishing big volumes of databooks and even more datasheets. At least all basic chips that ever made it into production (and ...


9

JackSprat was a tool produced by a company called Brayder, used to remove portions of the original ROM images. It used to produce a ROM backup along with a PRC which could be used to restore it; you can still find the original manual on the Internet Archive's copy of Brayder's technical support page. Without that ROM backup and the associated restore PRC, ...


9

I think one reason that it is very prolific, is that JDV is right: in many cases the rightsholders may not have any interest in pursuing legal interests. And in the case of very old games and companies (that may not exist any longer) that is probably true. Nintendo however, has some very specific things to say about this on their corporate legal page: ...


9

I feel like you're remembering the Apple At Play disk that came with the Apple //c. It had Lemonade Stand, Quick Quiz, and Space Quarks (more of a Galaxian clone than Space Invaders, but I didn't know Galaxian when I was young, so I compared it to Space Invaders, too). On Windows 10, I use AppleWin, which is really a //e emulator, but it has all the ...


9

A typical EPROM series of that period is the 27xx series. Today's DIL EEPROMs still use the same pin layout. Access time varied with models. Datasheets with exact dates are difficult to google systematically, but for example, an Intel 2764A-250 had a 250ns access time in 1983, while the 2764A-1 variant had a 180ns access time in1989. So the ballpark is "...


9

A ROM, short for Read-Only Memory, is computer chip with bits stored in it. Unlike RAM chips, the bits are persistent (remain when the power is turned off) and (usually) require a special programming process to change them. An arcade machine of 80s or 90s vintage is just a computer (often a custom-built, somewhat special-purpose computer) which reads the ...


9

However, the TI cartridges could also contain a different type of ROM called "GROM". Which I believe was "Graphics ROM". Jup, although, it wasn't really related to graphics at all. More due the fact, that its primary usage within the TI99/4 was to hold GPL code - which itself stands for Graphic Programming Language. There was also GRAM, if memory serves, ...


8

I don't remember any embedded games, but I would highly recommend Virtual II (http://www.virtualii.com/) for Apple II emulation. Its free if used in a limited fashion, otherwise you need to buy a license, but it does just about everything you could possibly think of. As far as a short-cut for access to the 'source code', the only thing I can think of is ...


8

Only the U26 and U27 ROMs provided by The Internet Pinball Database differed between versions. Here is an image representing some results of that analysis: Red, green or blue means that the byte was different only in version L-1, L-3 or F-1 respectively. White means that the byte was the same in all, and grey none. The upper half is U26 and the lower half ...


8

With the information in pndc's answer to this question I've been able to examine the various ROMs and I think I have the definitive answer. Firstly it seems that CDTV and CD32 do things slightly differently so I'll examine them separately. Background The commented disassembly of Exec by Markus Wandel provides some very useful information. In particular, it ...


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