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To understand what was going on with licensed and unlicensed ports of popular arcade games in the 1980s, you have to understand two critical factors. The video gaming culture of the time, and the preeminence of coin-op arcade games. The role of trademarks and legal trademark protections, which was the more crucial law pertaining to arcade game ports at the ...


11

As a personal project I had the idea to create a custom cartridge for my Commodore 64 and use an ATmega 1284p microcontroller to emulate eproms and/or custom chips. I doubt that this will work! The reason is simply the time needed by the microcontroller to react on a signal change: As far as I know, you have about 0.25µs to react on some edge on the C64 ...


10

Under the hood, the NES was almost identical to the Famicom, its Japanese counterpart released in 1983: image source The Famicom console itself was much smaller that the NES, and it had a traditional top-loading cartridge slot instead of the NES's notoriously unreliable front-loader. It's cartridges were also more reasonably sized: Image source At the ...


10

The price difference was indeed entirely in the packaging. The important thing to remember about mask ROMs is that, though the setup costs and lead times were high, they had the lowest marginal cost of any form of memory. The reasons behind this are fairly clear if you look through this ROM, EPROM, & EEPROM Technology document from Integrated Circuit ...


9

extend [...] with boards like this one It might be notable, that the mentioned X-pander-3 is a rather new and comfortable solution. Many extenders, as they were called back then, were much less capable, often barely a switch to enable power to either cartridge. Typical examples are Apotek's Aprospand-64 Cardcos CARDBOARD/5 Various Extenders from Rex ...


9

Initial assumption you are making about the signals /GAME, /EXROM, R/W, and the clock are reasonable. There are some nuances with the other signals that you might need to consider. The C64 has the ability to map the 4K of addess space at D000-DFFF as either system RAM or I/O. The only way your cartridge can know which one is mapped is using the /IO1 and /...


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

The code for the decompression system has been decompiled and partially commented here. Essentially the compression used is a form of run-length encoding, with a few modifications to make it more efficient for Gameboy graphics. The main improvement is that graphics are split into bitplanes rather than being compressed as single bitmaps. That is, each pixel ...


8

According to the Iwata Asks for G/S, Iwata created compression tools for the graphics in G/S (as well as other parts of other Pokémon games). Morimoto: What's more, there were the tools for compressing the Pokémon graphic code… Iwata: Ah yes, the compression tools. Morimoto: You were kind enough to create those tools. Iwata: Yes. (...


7

Although not an extender in the true sense as it only had one cartridge port, the Magic Voice expansion allowed game cartridges plugged into it to take advantage of its abilities to provide speech in games. This ended up only being used by the Wizard of Wor and Gorf titles. However, it is technically two cartridges working simultaneously that an "end user" ...


7

This is basically a duplicate for NES cartridge ROM emulation with Arduino or Pi?. The fact that the C64 is a bit slower doesn't change it in any way, so you might want take a look at the answers - as well as Martin Rosenaus's fitting answer. To pull something like this off, you need a MCU about 15-25 times faster than an ATmega (using assembly, make that ...


6

The mechanical aspects of the NES require that all NES Gamepaks be about the same size. NES could not predict with certainty everything that game designers might want to include in a Gamepak, and were more interested in ensuring that the cartridges could handle the worst-case need than in making them as small as possible. Making the cartridges larger would ...


5

The most common usage for an expansion bus extender was to simply eliminate the wear-and-tear on the computer's expansion connector from frequently swapping cartridges in and out. Instead, the expander offered a more "sacrificial" connector for this purpose, and could more easily be replaced if the connectors wore out. The most common case I know of for ...


5

For the most part these games were just not big enough to be noticed or cared about. Acorn computers were mostly sold in the UK and were never as popular as their rivals, for example. If the arcade developers, most of whom were Japanese or American, even knew of those knock-offs they would have had to take legal action in the UK. In the 80s that was even ...


4

asserting /GAME on the cartridge port of the C64 leaves three blocks of the C64 address space "unmapped" No, at least not alone. /EXROM also needs to be high. Otherwise standard RAM/ROM configuration prevails. Is it safe for the cartridge to respond to read and write requests to these areas? Yes. I assume here that the cartridge would have its own ...


3

There's a recent improvement in C64 fast loading technology made by Linus Åkesson. The main idea is to decode GCR inside 1541 thus gaining more transfer speed. An introductory article into the problems of GCR decoding inside 1541 (with the memory for both code and data of just 2048 bytes) is here: https://www.linusakesson.net/programming/gcr-decoding/index....


3

Here are the ones I've come across: SDOS V1.1, a "C64 disk utility and speed loader," which has had development done on it as recently as 2019. According to the readme, it's "Public Domain: open-source and freeware." It's based on earlier programs "VDOS" (1986), "SJLOAD (v0.96)" (2008-2009) and "SDOS (v1.0)" (2016). I discovered it on csdb.dk, but the ...


3

I see no reason to believe that the Pokémon Red cartridge (nor the Green one) is fake. Why they're not fake The small portion of the outer cartridge and labels in your picture shows a high standard of printing on both labels, far better than that which I've seen on fake cartridges myself. The fact that the battery may have been replaced isn't an indicator ...


3

From our perspective today, it seems surprising that major companies engaged in wholesale copying of the basic designs of each other's games and only really bothered changing the names of them, but the simple fact is that at the time, it had not been legally determined that such behaviour actually could be copyright infringement. Every country had its own ...


2

Action! is a programming language for the Atari 8-bit line. It was never ported to the Atari ST. I can't find a ROM of the cartridge, but the Internet Archive does hold printed manuals for the language as well as its source code, which was released under the GPL by Action! author Clinton Parker. Manual (2018 edition): https://archive.org/details/...


2

I found a .crt file for Final Cartridge III on csdb which I could start by attaching it as generic CRT cartridge, but I assume installing via the predefined way might provide better integration? The difference is only with a "raw" image, vice has to know the layout of it. If you have a .crt file, generic should be ok. See also http://vice-emu.sourceforge....


2

If you examine the cartridges produced during the active life of 8-bit computers, then first of all you need to look at the Japanese and MSX. One-, two-, three-megabit cartridges with mappers were produced in rather large editions - in general, the picture was similar to the one that Sega had for the Master System. Megabit ROM Cartridges


2

As Raffzahn points out, because memory can be bank-switched in the address space available to cartridges, the maximum size is limited only by the intersection between the technology available and how expensive and physically large you're willing to make the cartridge, and how you're willing to power it. Nonetheless, you're probably thinking of cartridges of ...


2

To add to user Raffzahn's answer - this It generates RAS/CAS signalling for each and every access, no matter what address is used (*1). would imply that - talking about a system without any cartridges inserted - when a Program writes to the I/O area, for example some VIC or CIA hardware register, RAM memory in the $Dxxx area gets clobbered. Unless I'm ...


2

There is most definitely no technical reason. And since some NES games featured different colours than just grey (think Zelda), it can't be based on some licensing directive either. Once the forms for the enclosure are made, there is no substantial cost in choosing any specific colour. Japanese games do show this quite nice. So there can't be no financial ...


1

The CARDBOARD/5 was an expansion unit released no later than 1985. Appendix A of its manual discusses enabling more than one cartridge at once. They mention 80-column display interfaces and IEEE-488 bus interfaces (for connecting to PET peripherals) as usable simultaneously with other cartridges. They provide a detailed description of handling the situation ...


1

The largest ROM space the Atari 2600 could address was 4K. But a number of bank switching schemes (and some fiendishly clever ways to do it cheaply!), allowed carts up to 32K. Although really there's no limit, you can always amend the bankswitching to allow more. This applies to all consoles, and computers. With bankswitching, possible with all ROM-based ...


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