What's so special about the 68000?

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I don't understand the hype around this chip. It's basically a glorified 8086, but with more registers, and 32-bit instructions. The data bus and ALU are still 16-bit, and it still has the slow 4 cycle bus access. Most of the registers are wasted on getting around the slow data bus, and the jump between 8-bit and 16-bit instructions is a much larger performance leap than going from 16-bit to 32-bit.

I'm not sure about the technical aspects of it, but for me the 68000 is a very special processor just becuase it was used in a lot of great computers and consoles, like the Genesis/MegaDrive, the Commodore Amiga computers, the Atari ST computers, and.... of course the Sharp X68000. Am I forgetting some? Probably. Here: https://en.wikipedia.org/wiki/Motorola_ ... plications

And it says on Wikipedia that the Intel 8086 started the whole 16-bit computing on the IBM PC, and was one of their most profitable sales yet. So that's good. Consider this, however.

The Amiga computers were more expensive than the IBM PCs!

Why? Well because they did use the m68k, and I think Apple might have used those at one point, too. It was still techincally superior. However, in the PC market back in the day, I think more people were going for IBM PC compatibles, and there was also more software written for x86, which is a 16-bit processor. So while you could install Windows 3.1 up to 98 on those machines with MS-DOS, people used GEM on the Atari, and Kickstart and Amiga OS on the amiga, which weren't as popular anyway. So the x86 like was more successful with PC software, whereas the m86k took over the remainder of the market with gaming, and Apple and Amiga users. They targeted them instead of IBM PC users.

And it was partly the 68000 chip the defined the whole 16-bit era in general, along with whatever the SNES and TurboGrafx-16 used. So I guess the m68k must have been cheap enough for companies to use, but also very performant, causing their aproducts to become in high demand, too. It was probably a market-related thing. Anyway, I'm not sure how it technically compares to the 8086, but maybe you can insight me.

It was an amazing chip for its time. It was first released in 1979, but it was used for all sorts of things even 20 years later! It powered the Sega Genesis/Megadrive, the Amiga, the Atari ST, the Neo Geo, the Capcom CPS 1/2 arcade platform, several of the early Macintosh computers... It was an awesome CPU for running fast-paced arcade-style games, and it wasn't too bad for general computing use either. Unfortunately, the limits of its architecture caught up to it by the mid 90s, so they weren't able to make a 68k architecture chip that could compete with the latest x86s or the various RISC architectures that were becoming popular at the time (such as MIPS, PowerPC, ARM, etc.), but despite that, it was still a fairly popular chip for 2D arcade games up until the early 2000s, when the CPS2 and Neo Geo platforms died out.

It was used in the Atari Jaguar although the system was technically (conntroversial) the first mass produced 64-bit system on the market.

The 68000 used in the Jag was just supposed to be used to coordinate the other CPUs, but a bunch of lazy developers decided to use it as the main CPU for their games instead.

I enjoyed the genesis/megadrive quite a lot as a kid

If you have never emulated it, give it a try

some good games for it are:
revenge of shinobi
buck rogers countdown to doomsday
golden axe
star control
rings of power
thunderforce 4

See, everybody just believes the Sega Genesis's CPU is faster than the SNES, with all faith, no proof. Everybody thinks you need to deliberately apply slowdown to get things to run properly, without ever questioning the reason why.

I'm impressed by your knowledge of the Atari Jaguar.

My 68000 Programmers' Guide includes an assembly-level command called "ILLEGAL".

That alone gets my vote!

Thank you. I don't remember where I read it, probably a thread on 4chan's /vr/ board, but I find it to be kind of interesting. It makes sense too, since I used to play around with a Jaguar emulator (Project Tempest, to be exact), and all the games that actually worked where more or less like 16-bit titles. Almost none of the actual 3D games I tried worked, though 2.5D games like Wolfenstein 3D and Doom seemed to work OK.



As much as I like the SNES, the Genesis had a MUCH better CPU. Play Gunstar Heroes or Red Zone some time, and you'll know what I mean. The SNES could probably do those games with the SuperFX chip, but NOT on the stock hardware.

Another really good example is Alien Soldier:

It seem they were not necessarily lazy. Using the Tom and Jerry CPU/GPU (Whatever they were really...) as main CPUs got developpers through a situation in which the gameplay,AI,graphics and sounds all came to clash with each other and prevented the games to work properly.
http://forums.penny-arcade.com/discussion/177756/the-terrible-tales-of-the-atari-jaguars-checkered-flag-and-fight-for-life


If you're interested I found TvTropes to be a great source of information about those things.
http://tvtropes.org/pmwiki/pmwiki.php/Main/VideoGameSystems
http://tvtropes.org/pmwiki/pmwiki.php/Trivia/CentralProcessingUnit


The slow 8 bits bus propably didn't help the snes either.

The Snes CAN run Gunstar Heroes. The CPU comparison is a bunch of BS.

That's kinda neat, but I'd really like to see how it runs with all the background details and everything, or how it handles some of the boss fights.

Interestingly enough, Treasure, the company behind Gunstar Heroes and Alien Soldier, was actually formed by ex-SNES developers from Konami. They themselves said in an interview that Gunstar Heroes couldn't be done on the SNES hardware, though this was over 20 years ago and we didn't quite know as much about the SNES hardware back then as we do now. And like I said, I believe GH would be possible with the SuperFX chip, which homebrew has been developed for, but not the stock hardware. http://megadrive.me/2011/11/03/an-inter ... -treasure/

There's not really that many SNES demo's that use the FX-chip actually. There's a lot of SNES demo's that run on stock hardware that people mistake as using an FX-chip.

I know. I'm just saying that SuperFX demos do exist.

Could the SuperFX chip really help to put more actions on screen!? It was mostly used for polygonal graphics and some special effects; the SA1 chip, used in Super Mario RPG and acting as a second CPU for the snes, make more sense for such a use to me. Though I don't know that much about electronics...