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| Otto Sykora... |
 Posted: Sat Aug 15, 2009 4:02 am |
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For small embeded unit 486 -sx I need to find some small distro .
All I tried did not work because they are apparently compiled only for
the 486dx (FPU missing).
any ideas what should I try |
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| Rene... |
| Posted: Sat Aug 15, 2009 4:58 am |
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Otto Sykora wrote:
Quote: For small embeded unit 486 -sx I need to find some small distro .
All I tried did not work because they are apparently compiled only for
the 486dx (FPU missing).
any ideas what should I try
uLinux or LFS?
Greetings,
Rene |
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| Juergen Beisert... |
| Posted: Sat Aug 15, 2009 6:30 am |
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Otto Sykora wrote:
Quote: For small embeded unit 486 -sx I need to find some small distro .
All I tried did not work because they are apparently compiled only for
the 486dx (FPU missing).
No problem, simply enable the fpu emulation in your kernel. It does not make
things faster, but work.
You should use a cross toolchain that only creates softfloat. It will run
your programs a litte bit faster, because it does not need an exception on
every FPU opcode.
jbe |
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| Otto Sykora... |
| Posted: Mon Aug 17, 2009 9:46 am |
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Quote: No problem, simply enable the fpu emulation in your kernel. It does not make
things faster, but work.
You should use a cross toolchain that only creates softfloat. It will run
your programs a litte bit faster, because it does not need an exception on
every FPU opcode.
No problem, for you fine, for me yes, have to learn first how to
compile kernel at all...;-)
I just realized that most finished distros , also the miniatur once
are meanwhile for 486dx minimum. |
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| Otto Sykora... |
| Posted: Mon Aug 17, 2009 9:47 am |
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ok will have look on those, DSL and similar today all need 486dx
minimum so as they are for download  |
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| Otto Sykora... |
| Posted: Mon Aug 17, 2009 9:51 am |
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Quote: Well, for old technology, you could run an old distribution.
well yes, but so old is the unit here not. It is brand new, but it is
486sx.
But it will need usb support etc, 2.4 kernel had this but 2.6x would
be much better in that for example. AFAIK bellow 2.4x there was no usb
support at all, so this might be a limit downwards.
the unit is 486sx, 300mhz, 128mb ram, something like PC104, but much
cheaper and kind of 'consumer' quality. |
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| Michael Schnell... |
| Posted: Mon Aug 17, 2009 1:16 pm |
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Otto Sykora wrote:
Quote: It is brand new, but it is
486sx.
But it will need usb support etc, 2.4 kernel had this but 2.6x would
be much better in that for example. AFAIK bellow 2.4x there was no usb
support at all, so this might be a limit downwards.
AFAIK, the 2.6 Kernel is configurable to support restricted hardware.
But maybe you need to configure and compile it yourself. So either you
compile the Kernel on a full featured PC or you use a restricted
distribution to boot the 486 and compile compile a 2.6 Kernel.
Debian can be booted from a very minimal Media and will bring up itself
completely from the Internet. (It takes some time to do that, but it's
fun  . ) I don't know whether this "minimal boot media distribution
supports 468 without FPU, but it's quite likely it does. You'll find
instructions on the Debian website.
-Michael |
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| Juergen Beisert... |
| Posted: Tue Aug 18, 2009 3:40 am |
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Otto Sykora wrote:
Quote: No problem, simply enable the fpu emulation in your kernel. It does not
make things faster, but work.
You should use a cross toolchain that only creates softfloat. It will run
your programs a litte bit faster, because it does not need an exception on
every FPU opcode.
No problem, for you fine, for me yes, have to learn first how to
compile kernel at all...;-)
I just realized that most finished distros , also the miniatur once
are meanwhile for 486dx minimum.
Maybe they enabled the embedded config option (CONFIG_IKCONFIG=y) in their
kernels. Read the help of the corresponding menu entry (run "make
menuconfig" in your own kernel tree, enter "/", then enter "IKCONFIG" to
get an idea where this menu entry is). Extract the config of their kernel
as mentioned in the help text and use it as a template in your own kernel
tree.
Next enable "[ ] Math emulation" (in menu "Processor type and features"), to
get a "CONFIG_MATH_EMULATION=y" in your own .config file. Build this
kernel, run it and be happy. Hmm, and you should select "Processor family
(486)". BTW: You can build this kernel with your host compiler. Kernel's
build system will instruct the compiler to only use opcodes the 486 is able
to handle (even if your host is a new shiny XYZ-Pentium-Opteron).
jbe |
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| Juergen Beisert... |
| Posted: Tue Aug 18, 2009 3:46 am |
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Otto Sykora wrote:
Quote: uLinux or LFS
ok will have look on those, DSL and similar today all need 486dx
minimum so as they are for download
Not exactly: They need at least a 486 CPU. But they do not enable the FPU
emulation in their kernel, that is why they need a 486dx. It's only the
CONFIG_MATH_EMULATION symbol in their kernel configuration that is
still 'n'. All you need is "CONFIG_MATH_EMULATION=y".
jbe |
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| Otto Sykora... |
| Posted: Tue Aug 18, 2009 6:49 am |
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Quote: in their kernel configuration that is
still 'n'. All you need is "CONFIG_MATH_EMULATION=y".
OK, this is nice info, I am just reading some howtos for kernel
compiling, have some 'config' from similar system for compilation from
config script, so will try to modify or add this and see if I succeed.
Is that correct this way? Add it to the config for compiler and it
will be set so?
Well I am so far just a user, kernel etc did not much buther me so
far, but now I have to bite myself into it somehow. |
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| Otto Sykora... |
| Posted: Tue Aug 18, 2009 6:51 am |
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Oh many thanks, will try this.
I think I will now install a debian on one of my normal PC, experiment
there and then later try to adapt and install all into the embeded PC
when halfway thinking it works. |
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| Helix... |
| Posted: Sun Aug 30, 2009 2:29 am |
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Otto Sykora ha scritto, Il 15/08/2009 12:02:
Quote: For small embeded unit 486 -sx I need to find some small distro .
All I tried did not work because they are apparently compiled only for
the 486dx (FPU missing).
any ideas what should I try
KaeilOS embedded linux supports also Vortex86SX
http://www.kaeilos.com
http://www.kaeilos.com/?q=download
happy hacking
--
helix |
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