Linux on 16-bit processors

Linux on 16-bit processors

[micklweiss]

I'm interested on running Linux on some less powerful, cheaper 16 bit
systems. I would like to know if there is a slimmed down version of the kernel (any
version 2.2+) that can run on 16-bit CPUs. I know that linux "requires" a
32-bit CPU, but I know that it has run on less. I'm interested in any arch -
really. 
I can't seem to find a slimmed down version of the kernel. Any projects out
there? Something with decent performance would be cool too. :o)

I'm not apart of the list, so if you could pleace CC: any replies to this
e-mail (micklweiss@gmx.net) that would be great.

I asked before at a local user group (southflorida embedded user group)..
and this is what info they got me. I just cut-n-pasted.

<cut>

To: Mick Weiss
From: "wblake@emsys.net" <wblake@emsys.net>

glad to help. you have interesting research.
Most handhelds these days are 32 bit processors, even pagers. Mostly some
ARM variant especially Intel StrongArm.

The main obstacle to running Linux on smaller (cheaper) CPUs seems to be an
MMU which Linux and most Unixes expect. For a Linux work alike, some RTOS's
will have various POSIX layers corresponding to  standard C library,
real-time facilities, threads, and shell utilities. So if an application
uses POSIX compliant calls, it can move from *ix to one of these operating
systems.
Most *Ix work alikes Lynx, and QNX claim POSIX compliance. Likewise
embedded RTOSes like Red Hat eCos, rtxc, mentor ati nucleus, vrtx, vxworks
etc. 
Even Microsoft supports many of these POSIX interfaces as do other non Unix
OS's like Digital (now HP) VMS, IBM MVS, IBM VM etc 

http://www.embedded.com/story/OEG20010312S0073

Original Message:
-----------------
From:  micklweiss@gmx.net
Date: Tue, 18 Mar 2003 14:39:45 +0100 (MET)
To: emsys@emsys.net
Subject: 


Lineo supports processors in the following specific architectures: 

32 bit with memory management 
32 bit without memory management 
16 bit/ 16 bit DSP 
8 bit processor/ 8 bit controller 

and uclinux is a whopping $200 (its whopping when your just messing with it
on your spare time ;), plus I'm not sure how its licenced (GPL?).

----

after searching I found a few things on RTLinux and linux on handhelds, but
-- oh well I'll keep looking (its only for myself, no business reasons, so
its not important)

miniRTL (after porting it) may be a good design to work from, I'll just have
to see.

Thanks Wil for all the info, It definitly sounds cool. I am looking into it
right now.

See you at the next meeting,

- Mick

-- 
(o> Web developer / designer
( )     UNIX Systems Admin
---   ~ www.mickweiss.com ~

</cut>

Thanks in advance for any help,

- Mick

(o> Web developer / designer
( )     UNIX Systems Admin
---   ~ www.mickweiss.com ~

-- 
+++ GMX - Mail, Messaging & more  http://www.gmx.net +++
Bitte lächeln! Fotogalerie online mit GMX ohne eigene Homepage!

Re: Linux on 16-bit processors

[Joel Jaeggli]

try elks:

http://elks.sourceforge.net/

the economics aren't really there as far as I can tell given the cost of 
embeded 386 and 486 class cpu's to say nothing of tiny powerpc and arm 
cpu's.

joelja

On Wed, 19 Mar 2003 micklweiss@gmx.net wrote:

> I'm interested on running Linux on some less powerful, cheaper 16 bit
> systems. I would like to know if there is a slimmed down version of the kernel (any
> version 2.2+) that can run on 16-bit CPUs. I know that linux "requires" a
> 32-bit CPU, but I know that it has run on less. I'm interested in any arch -
> really. 
> I can't seem to find a slimmed down version of the kernel. Any projects out
> there? Something with decent performance would be cool too. :o)
> 
> I'm not apart of the list, so if you could pleace CC: any replies to this
> e-mail (micklweiss@gmx.net) that would be great.
> 
> I asked before at a local user group (southflorida embedded user group)..
> and this is what info they got me. I just cut-n-pasted.
> 
> <cut>
> 
> To: Mick Weiss
> From: "wblake@emsys.net" <wblake@emsys.net>
> 
> glad to help. you have interesting research.
> Most handhelds these days are 32 bit processors, even pagers. Mostly some
> ARM variant especially Intel StrongArm.
> 
> The main obstacle to running Linux on smaller (cheaper) CPUs seems to be an
> MMU which Linux and most Unixes expect. For a Linux work alike, some RTOS's
> will have various POSIX layers corresponding to  standard C library,
> real-time facilities, threads, and shell utilities. So if an application
> uses POSIX compliant calls, it can move from *ix to one of these operating
> systems.
> Most *Ix work alikes Lynx, and QNX claim POSIX compliance. Likewise
> embedded RTOSes like Red Hat eCos, rtxc, mentor ati nucleus, vrtx, vxworks
> etc. 
> Even Microsoft supports many of these POSIX interfaces as do other non Unix
> OS's like Digital (now HP) VMS, IBM MVS, IBM VM etc 
> 
> http://www.embedded.com/story/OEG20010312S0073
> 
> Original Message:
> -----------------
> From:  micklweiss@gmx.net
> Date: Tue, 18 Mar 2003 14:39:45 +0100 (MET)
> To: emsys@emsys.net
> Subject: 
> 
> 
> Lineo supports processors in the following specific architectures: 
> 
> 32 bit with memory management 
> 32 bit without memory management 
> 16 bit/ 16 bit DSP 
> 8 bit processor/ 8 bit controller 
> 
> and uclinux is a whopping $200 (its whopping when your just messing with it
> on your spare time ;), plus I'm not sure how its licenced (GPL?).
> 
> ----
> 
> after searching I found a few things on RTLinux and linux on handhelds, but
> -- oh well I'll keep looking (its only for myself, no business reasons, so
> its not important)
> 
> miniRTL (after porting it) may be a good design to work from, I'll just have
> to see.
> 
> Thanks Wil for all the info, It definitly sounds cool. I am looking into it
> right now.
> 
> See you at the next meeting,
> 
> - Mick
> 
> 

-- 
-------------------------------------------------------------------------- 
Joel Jaeggli	      Academic User Services   joelja@darkwing.uoregon.edu    
--    PGP Key Fingerprint: 1DE9 8FCA 51FB 4195 B42A 9C32 A30D 121E      --
  In Dr. Johnson's famous dictionary patriotism is defined as the last
  resort of the scoundrel.  With all due respect to an enlightened but
  inferior lexicographer I beg to submit that it is the first.
	   	            -- Ambrose Bierce, "The Devil's Dictionary"

Re: Linux on 16-bit processors

[J.A. Magallon]

On 03.19, micklweiss@gmx.net wrote:
> I'm interested on running Linux on some less powerful, cheaper 16 bit
> systems. I would like to know if there is a slimmed down version of the kernel (any
> version 2.2+) that can run on 16-bit CPUs. I know that linux "requires" a
> 32-bit CPU, but I know that it has run on less. I'm interested in any arch -
> really. 

http://www.uclinux.org/

It doesn't need an mmu, boots on a Palm. ;) Look  in 'uClinux Ports'

Or http://www.linux.org/projects/ports.html, look for m68k ports, don't know
if any of them work on cpus below 68020.


-- 
J.A. Magallon <jamagallon@able.es>      \                 Software is like sex:
werewolf.able.es                         \           It's better when it's free
Mandrake Linux release 9.1 (Cooker) for i586
Linux 2.4.21-pre5-jam0 (gcc 3.2.2 (Mandrake Linux 9.1 3.2.2-3mdk))

Re: Linux on 16-bit processors

[Xavier Bestel]

Le mer 19/03/2003 à 01:27, J.A. Magallon a écrit :
> On 03.19, micklweiss@gmx.net wrote:
> > I'm interested on running Linux on some less powerful, cheaper 16 bit
> > systems. I would like to know if there is a slimmed down version of the kernel (any
> > version 2.2+) that can run on 16-bit CPUs. I know that linux "requires" a
> > 32-bit CPU, but I know that it has run on less. I'm interested in any arch -
> > really. 
> 
> http://www.uclinux.org/
> 
> It doesn't need an mmu, boots on a Palm. ;) Look  in 'uClinux Ports'
> 
> Or http://www.linux.org/projects/ports.html, look for m68k ports, don't know
> if any of them work on cpus below 68020.

It works on an Amiga 500 (plain 68000).

	Xav

Re: Linux on 16-bit processors

[Alan Cox]

On Tue, 2003-03-18 at 23:46, micklweiss@gmx.net wrote:
> I'm interested on running Linux on some less powerful, cheaper 16 bit
> systems. I would like to know if there is a slimmed down version of the kernel (any
> version 2.2+) that can run on 16-bit CPUs. I know that linux "requires" a

The kernel side is fairly easy if you have a couple of megs of ram. The
ucLinux tree supports mmuless systems and a fair variety of processors. 
User space is more of an issue. The standard Linux userspace is designed
for systems with disks and paging, the uclinux stuff is smaller and the
ELKS userspace is tinier still.

And uclinux is free not $200. Maybe the writer is confused with the 
ucSimm development board ?

BTW are "real" 16bit processors actually cheaper any more ? 16bit keeps
costs down but several 683xx processors seem to use 16bit external
data bus as do some ARM.


Alan

Re: Linux on 16-bit processors

[H. Peter Anvin]

Followup to:  <1048084009.30751.23.camel@irongate.swansea.linux.org.uk>
By author:    Alan Cox <alan@lxorguk.ukuu.org.uk>
In newsgroup: linux.dev.kernel
> 
> BTW are "real" 16bit processors actually cheaper any more ? 16bit keeps
> costs down but several 683xx processors seem to use 16bit external
> data bus as do some ARM.
> 

80186 seems to be going strong, still; and EZ80 is available as a
synthesizable core (basically a Z80 with a 24-bit addressing mode and
a very primitime MMU.)

	-hpa
-- 
<hpa@transmeta.com> at work, <hpa@zytor.com> in private!
"Unix gives you enough rope to shoot yourself in the foot."
Architectures needed: ia64 m68k mips64 ppc ppc64 s390 s390x sh v850 x86-64

Re: Linux on 16-bit processors

[Greg Ungerer]

Hi Mick,

> I'm interested on running Linux on some less powerful, cheaper 16 bit
> systems. I would like to know if there is a slimmed down version of the kernel (any
> version 2.2+) that can run on 16-bit CPUs. I know that linux "requires" a
> 32-bit CPU, but I know that it has run on less. I'm interested in any arch -
> really. 
> I can't seem to find a slimmed down version of the kernel. Any projects out
> there? Something with decent performance would be cool too. :o)

You want uClinux, http://www.uclinux.org.


> I'm not apart of the list, so if you could pleace CC: any replies to this
> e-mail (micklweiss@gmx.net) that would be great.
> 
> I asked before at a local user group (southflorida embedded user group)..
> and this is what info they got me. I just cut-n-pasted.
> 
> <cut>
> 
> To: Mick Weiss
> From: "wblake@emsys.net" <wblake@emsys.net>
> 
> glad to help. you have interesting research.
> Most handhelds these days are 32 bit processors, even pagers. Mostly some
> ARM variant especially Intel StrongArm.

Allmost all Palm's use a Motorola 68k varient (either
68328, 68EZ328 or 68VZ328). These have no MMU.


> The main obstacle to running Linux on smaller (cheaper) CPUs seems to be an
> MMU which Linux and most Unixes expect.

Nope. That is what uClinux is all about. Running Linux without
an MMU. We have been doing it for years. First supported on
kernels in the linux-2.0.x range. Most people using 2.4.x these
days, or now uClinux is part of standard linux, it is in all
the latest 2.5.x kernels.


[snip]
> Lineo supports processors in the following specific architectures: 
> 
> 32 bit with memory management 
> 32 bit without memory management 
> 16 bit/ 16 bit DSP 
> 8 bit processor/ 8 bit controller 
> 
> and uclinux is a whopping $200 (its whopping when your just messing with it
> on your spare time ;), plus I'm not sure how its licenced (GPL?).

Well this is most certainly wrong. uClinux is free. It is just
a set of patches against standard linux kernels, so it is,
offcourse, covered by the GPL. You can get all the code at
www.uclinux.org or under cvs at cvs.uclinux.org

Lots of MMUless processors support, including Motorola 68000/683xx
and ColdFire varients, ARM7TDMI cores (from Atmel, Conexant, Samsung,
NetSilicon, etc), NEC v850, Sparc LEON, Intel i960, Hitachi H8/300,
MIPS (MMUless varients, for example from Brecis), FPGA soft cores
(like Altera NIOS, OpenCores OpenRISC, etc).

Regards
Greg




------------------------------------------------------------------------
Greg Ungerer  --  Chief Software Wizard        EMAIL:   gerg@uclinux.org
SnapGear Pty Ltd                               PHONE:    +61 7 3435 2888
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