Commodore 256 under construction

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I started out with a superboard II in the late 1970s and I have to say that modern systems are easier to program. Our systems are less constrained by limited resources. Our data is more persistent. The languages are better.

Young kids might have been more creative back when we had a 4k 6502 to play with, but you can’t say that programming was easier then.


4k 6502? Luxury. I had to work 29 hours a day programming MMORPGs on a Jacquard loom.


But in the 1960s I would have killed for a loom. We had to hand code machine code on paper tape and carry it 50 miles in the snow to test it, then lug it home when it didn’t work.


But you try and tell the young people today that … and they won’t believe you.


It looks a lot like what Apple did in 1988, except decided to support only Macinosh line, and stopping the production, making IBM and compatibles makers really happy.

Biggest problem I see, of course is the SID chip, it could be of course emulated with an FPGA. Having to retain compatibility mens that one have to emulate it rather than to go with more interesting design. Like the Ensoniq chip of the Apple IIgs or even the OPL-3 made by Yamaha


A more interesting design experiment (to me) would be design an “IBM PC” killer. Every 8 bit aficionado laments the PC hegemony. What would have been necessary for Tandy, Commodore or Apple to successfully compete with the PC?

  • a thorough understanding of the importance of backwards compatibility, and a substantial commitment to the platform
  • availability of a CPU that enables such. The Z8000 wasn’t backwards compatible, and the 65c816 was too late.
  • a viable Lotus 1-2-3 competitor

It still would have been quite tough. Competing against IBM is one thing but that clone market was nasty: Compaq, Dell, Gateway and the Taiwanese…


Ironically enough, one of the most approachable early 16-bit systems was… the IBM PC. It had BASIC in ROM, like most of the old 8-bit systems, and in its early days, it had a very well-documented BIOS.

Of course, “simplicity” is relative - add-in cards were not “plug and play” (remember setting IRQs?), and of course there were multiple incompatible video display options. CGA left a lot to be desired, and the standard monochrome adapter didn’t support graphics. Not to mention, sound hardware was not standardized, and early graphics cards lacked anything sophisticated like sprites and such.

@Mike.71 made a great point about the Apple IIGS. I ever-so-sorely wish that Apple had gone that direction instead of the Macintosh (less Jobs, more Woz). I grew up with a II+, and the GS would have been perfect if it hadn’t been so late.


Sounds like someone’s having fun.
Having moved from a ZX Spectrum to an Amiga, I will agree with your assessment of the Sinclair QL (and the quaint tape drives with a massive 85K storage… they were so cute, though!). I do think you’re being a touch unfair about the Amiga. At the time, a 256 colour screen powered by a pre-emptive multi-tasking operating system that only needed 256K to run was not something to be sneezed at. In contrast, there was IBM’s OS/2, which needed 4Mb when PCs typically had a limit of 1Mb, courtesy of that **$#! awful x86 segmented memory architecture.
Commodore’s bad management killed the Amiga; not vice versa.


It was a glorious machine. Not that I was much of a programmer. I agree that it was an evolutionary branch, lost.

I think Apple did it, and is called Macintosh. Add in a new computer an emulation layer and some peripheral compatibility.
Commodore tried it with the C128, but failed with the Amiga, even if a software emulator was made.

Actually IBM did something similar witj PS/2 and i386 processor. PS/2 boards had a real mode and a protected mode BIOS

I understood that, oddly enough, the Amiga was effectively the successor to Atari’s 8-bit line of computers, and that the people behind the C64 ultimately made the Atari ST. Wikipedia refers to Shiraz Shivji.

In other news, I hear the 1541-Ultimate II+ is the new hotness for C64 users.

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I’m pretty sure the Amiga was 32 bit, not 16. Not sure where that came from.

Also, I though I’d point out the c65gs which is a part of the mega65 project–or at least related to. The idea is to implement the C65 in an FPGA. I think they’re working on the full hardware for the system–keyboards, cases, etc.


I wonder how good the disk interface is for this machine? One of the things that hobbled the C64 was its completely braindead floppy interface.

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No way. Not even close, really. I seem to recall that the machine had a moment in the sun in the early 80s, and understandably fanatic devotion from owners due to its innovative features, but got blown out in sales by the IBM PC as soon as sound boards for the PC hit the market.

According to the Intertubes, the claim that Commodore was the “best selling computer line in history” seems to be based on exaggerated claims made by Commodore founder Jack Tramiel in 2007 - that he admitted at the time to be wild guesses.

Even if you only count machines after the 286 and before the x86_64 architectures it seems pretty obvious that the PC is the best selling computer line in history.


They did directly compete with the PC clone market with the PC-10 line:


I really enjoy retro systems. My first computers were an Atari 800 XL, C-64, C-128, and Apple IIe. Recently I have been interested in mechanical calculators.

That being said, enough. Your hobby computer is the Raspberrypi and your programming language is Python. Or better yet build a MOS 6502 computer by hand. It is much more satisfying. How about an Ardiuno? Build a sensor or a robot.

There are emulators if you want to get your retro on. These products are a waste. Enough.

the 68K was available when the first IBM PC was around. But it was quite expensive. The 68008 would have been ideal for re-using a lot of 8-bit peripherals and keeping costs down, but it wasn’t out until a 1982, a year after the IBM PC’s release. Even so, it would have been significantly costly to use a 68K in a machine in the early 80’s.

6809 was also around at that time, but I lacked the wider addressing that was present in the 8086/8088. The 6809 did end up in the Tandy CoCo, but it was too late to do much about the PC’s dominance.

Overall I think having an open architecture with off-the-shelf components is one of the important factors in the success of the PC. The open architecture lead to the combination of big businesses buying IBM’s and home users buying the much cheaper and often more capable clones.

Fierce competition had smaller shops competing on price, and larger shops trying to innovate new features. Ultimately consumers ended up with high-value system. But if you recall that late 80’s to late 90’s era, our PCs were becoming obsolete almost as fast as we could replace them. The market and technology moved so fast. Stuff got really cheap and with that you could afford a much more powerful system.

Honestly if there was a good 16-bit x86 emulation on a PowerPC, software or hardware, we could have switched in the mid-90’s. The patents were out on the 8086 by then, and much of the DOS world was still 16-bit. The introduction of Windows 95 really moved everyone to 32-bit, and it the potential legal complications for supporting 32-bit x86 without a license from Intel wouldn’t have gone away until early 2000’s. (386DX was out in 1985)

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How many SID chips will it contain I wonder? Sure, you definitely need 2 of them for stereo. But why stop at just 2?

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Here you go. Go crazy!

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