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Minix no longer quite so mini

Minix no longer quite so mini

Posted Mar 8, 2012 11:35 UTC (Thu) by epa (subscriber, #39769)
Parent article: MINIX 3.2: A microkernel with NetBSD applications

I remember when Minix consciously limited itself to compatibility with Unix Seventh Edition, which was "an improvement on all previous and subsequent versions". The new userland completes Minix's transition from a toy system which was the most Unix-like you could get on horribly limited hardware (a 16-bit PC with 640Kbyte RAM, no MMU and perhaps even no hard disk) to an OS focused on real-world use.

It is no longer necessary for every process to fit in 64 kilobytes of user memory!


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Minix no longer quite so mini

Posted Mar 8, 2012 18:00 UTC (Thu) by smoogen (subscriber, #97) [Link]

Sigh.. in the good old days you learned a lot trying to keep your program in 64k. How are the kids these days going to learn :).

Minix no longer quite so mini

Posted Mar 8, 2012 20:32 UTC (Thu) by iabervon (subscriber, #722) [Link]

That class of computer is actually quite popular with certain groups these days. There's a popular series of machines produced by the original designer, as well as a huge variety of compatible clones, and lots of peripherals available. Actually, you've got a high-end device if you've got 64k to play with; most of them just have 32k. Of course, I've yet to hear of people trying to run something Unix-like on an Arduino, but it's certainly a platform which needs low-resource programs and provides unusual benefits over platforms that aren't so constrained.

Minix no longer quite so mini

Posted Mar 12, 2012 4:25 UTC (Mon) by cmccabe (guest, #60281) [Link]

You could always run LUnix [ http://hld.c64.org/poldi/lunix/lundoc/lng.html ]. According to the website (updated 1997), "90% of the kernel are DONE !! :-)"

Minix no longer quite so mini

Posted Mar 12, 2012 19:23 UTC (Mon) by andreasb (subscriber, #80258) [Link]

Please, get with the times ;-) The *current* website (http://lng.sourceforge.net/lunix/lunix.html) was last updated in 1999 and LUnix has since been rewritten as LNG (http://lng.sourceforge.net/ last updated 2004).

It won't run on the mentioned Arduino of course since it's written for the 6510 CPU and peripherals in a C-64 or C-128.

Minix no longer quite so mini

Posted Mar 12, 2012 18:12 UTC (Mon) by leoc (subscriber, #39773) [Link]

Arduino. A low cost Uno board has 32kb of ram and is nonetheless quite popular.

Minix no longer quite so mini

Posted Mar 12, 2012 19:21 UTC (Mon) by Cyberax (✭ supporter ✭, #52523) [Link]

Arduino is hardly 'low cost'. For the price of an Arduino board with stone-age technology CPU one can get a nice real modern CPU with at least 4-16Mb of RAM.

Minix no longer quite so mini

Posted Mar 12, 2012 19:36 UTC (Mon) by andreasb (subscriber, #80258) [Link]

The µC on an Arduino Uno has only 2 kB of RAM. It does have 32 kB of on-chip program flash memory.

There's no real dynamic program loading possible (from connected storage or whatever) since it can't execute instructions from RAM. Unless you take the indirection of a script/bytecode interpreter or outright emulation of a different CPU (there's an AVR based CP/M project out there that emulates a 8080 with external DRAM).

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