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Comment by alxlaz | Hacker News Reader

I think one of the greatest things about the M68K today is that it's a relatively powerful processor that's relatively straightforward to program and it's pretty easy to design hardware that uses it.

A single board computer with the m68k is still small enough that you can comprehend the schematics and build it at home (e.g. http://www.kswichit.com/68k/68k.html ), and it's a very valuable learning experience.

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I used the 68K back in college for a couple of hardware/software codesign classes. It was a lot of fun and easy to work with. The boards we used were all wire-wrapped. No where near as clean as the kit you linked to. Still, was pretty easy to work with and fairly forgiving (I don't remember any of them burning up despite all of the crazy lab circuits we connected). Still have my Programmer's Reference Manual sitting on my shelf, sadly just collecting dust.

Also the processor the Sega Genesis uses, so you can learn to make your own Genesis game!

Gamehut has a series on doing that

https://youtu.be/PSYhSmXBgIw

Are new M68K chips still produced? I looked a while ago, but couldn't find any.

Barely. The 68SEC000 is still in production, but is NRND.

What about the second-source vendors? Historically I know there were Hitachi ("HD" prefix), Toshiba ("TMP" prefix), and Signetics ("SN" prefix) parts. At one point I saw a modern-looking Atmel data sheet for a TS68C000 (Thomson/STMicro license?), but I don't know how recent that actually was.

The Hitachi line, at least, seems to be explicitly EOL by Renesas. I'm not familiar enough with the other vendors to know who might have picked up their licenses.

I suspect those are all gone too. TS68C000 went EOL in 2010 -- it was produced by Thomson-CSF, which was acquired by e2v.

One interesting avenue to explore might be the Sega Genesis. It's still being produced in Brazil, believe it or not -- and there must be some sort of 68000-compatible processor at the core of those.

I think many was EOLed when the Freescale Sendai fab shut down.

I'd assume so, since there are still many devices that use them!

Yes. They're known as ColdFire processors now, and they're sold by NXP.

Coldfire is a rather different product, though. The instruction set is similar but not identical, and there's no exposed memory bus. (Most of the parts have internal flash and SRAM, like a modern microcontroller.)

> The instruction set is similar but not identical, and there's no exposed memory bus.

Actually, there are a number of offerings in the coldfire v2/v3/v4family with decent performance and external buses including PCI, 10/100 ethernet, USB, ATA, and CAN with DDR memory and parallel bus interface.

https://www.nxp.com/docs/en/data-sheet/MCF5307BUM.pdf https://www.nxp.com/docs/en/data-sheet/MCF54418.pdf https://www.nxp.com/docs/en/data-sheet/MCF54455.pdf

Oh, the modern ones absolutely have other external busses -- but not a standard 68000 memory bus. There's no way to hook up an EEPROM with your program on it, for instance.

I see what you are talking about. While the external bus interface on these cold fire parts is not a pin compatible m68k cpu bus, it certainly can access memory devices and uses DMA. From the 5307 manual:

1.3.7.1 External Bus Interface The bus interface controller transfers information between the ColdFire core or DMA and memory, peripherals, or other devices on the external bus.

I used one of the first generation dev boards, it had external DRAM and ROM.

Check out the Firebee. An Atari ST semi-compatible machine built around the Coldfire:

http://firebee.org/

NXP still makes a range of ColdFire-based chips, which is based on M68k

The 68K evolved into two lines: the Dragonball and, more recently, the ColdFire line. NXP is continuing production of the ColdFire parts. Dragonball evolved into the iMX line by swapping the 68K core for ARM.

https://en.wikipedia.org/wiki/Freescale_DragonBall

https://en.wikipedia.org/wiki/NXP_ColdFire

I've got one of these: http://apollo-core.com/index.htm in an Amiga. It's an insane amount of fun.

"Apollo Core 68080 is the natural and modern evolution of latest 68000 processors. It's 100% code compatible, corrects bugs of 680x0 designs and adds on top most of the cool features which were invented the years after."

Check this out. Apolle core should have a neon sign above it.

AFAIK, no, at least not for the general market, but they're pretty easy to get on Ebay, AliExpress & friends.

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