[En-Nut-Discussion] tftp boot with company DHCP server, and boot from SD card

[Harald Kipp]

Hello Hylke,

Faas, Hylke wrote:

> I was wondering is there a way to download a program into an Ethernut
> (3.0E) using DHCP without using tftp32 as DHCP server?  I know it is
> possible when setting tftp32 as a DHCP server, but to get access to the
> internet I have to use the "normal" DHCP server used for all the
> computers and other network systems and because of company policies I
> can't access internet or the other computers without using the DHCP
> server.

I understand this, actually I often got the same problem. Right now I'm
trying to find a free IP of a reserved pool and hope, that others a
smart enough not to use this address when booting up.

You may modify the bootloader to use a fixed image name, if DHCP doesn't
provide one?


> I was also wondering if someone already developed (or is developing) a
> boot loader for booting form SD card. If not maybe I'll give it a try.

Mh...difficult story. I definitely know, that at least one customer is
running such a solution. I advised him to create a Nut/OS application
for loading an image from SD Card into RAM and run it. I further know
that it is part of a final product and running in many hundreds of
systems. We recently tried to do the same with our online Ethernut
http://ethernut.microweb.org/
and failed miserably. No idea what went wrong. The RAM contents looked
fine but as soon as it jumped to address zero the Ethernut froze. After
several hours I gave up and decided to flash the webserver. It was quite
frustrating, because I don't have the slightest idea what was happening.

The advanced solution: At
http://www.ethernut.de/arc/
you'll find
umon-ethernut3-20070730.zip
which is an early release of
http://www.umonfw.com/
from Ed Sutter. As far as I remember, several thing had been working.
The bad news is, SD/MMC was not among them. Anyway, it's a very nice
bootloader and I always regretted not having more time to spend on this
nice software. There is also a mailing list and Ed is one of the most
helpful persons I know. Possibly you need to register yourself at
Lucent's website to get the code. But that's how big companies sometimes
deal with open source. It doesn't hurt and no one ever called me to sell
Lucent's products. ;-)

Harald