Robert Amstadt writes:
>
> ------==-==--==-==---=---======--===-=-=--=--=---=
> Mime-Version: 1.0
> Content-Type: text/plain; charset="us-ascii"
>
> >Whats it for? A specific purpose or just for fun?
>
> It is for a commercial product.
>
> >> 1. No root filesystem. Kernel image and process images would be stored in
> >> Flash memory ready to run. The kernel would start the init process which
> >> would in turn start the other processes.
> >
> >Why not just have the root file system in the flash memory?
>
> The problem is lack of memory. If each executable needs to be copied out
> of flash into ram, then it is very likely that I will not have enough ram
> in the system. At this point, it would not pay for me to put more ram in
> the system. Personally, I don't see why this should be such a hard thing.
> Granted, I haven't looked at the ELKS sources, but I suspect that it should
> be possible to add this feature in with a little effort. This is certainly
> something that could benefit nearly anyone that is trying to put ELKS into ROM.
>
> Should I decide to go foward with using ELKS, I won't expect any of the
> current developers to add this support. I will simply code it myself and
> submit the changes to the code maintainers. At this point, I'm just trying
> to assess how much effort is involved. If I can get ELKS to do the job
> without an excessive amount of investment of time, I would like to do it.
> I think the world needs a good ROMable OS.
The advent of nano-X and graphics under ELKS, together with this discusion
has set me thinking more seriously about ROMing ELKS.
In the bath last night (as always) I thought about how I could modify ELKS
so it would run without a filesystem, and came up with a way of storing
binary images in an area of ROM. The ROM would simply contain all the
binaries in minix format concatenated together, the header of each aligned
to a 16 byte boundary. The unused field of the header could contain a
4 character unterminated string which identifies the binary.
exec would then be recoded to search this area of ROM for the binary in
question, leaving the text segment and running it in place. The initialised
data would then have to be copied into RAM, but very little RAM would be
required as only the kernel and program data segments would need to be
stored there.
Any thoughts anyone?
Al
