On 2/14/08, David Hawkins <[EMAIL PROTECTED]> wrote: > Jon Smirl wrote: > > I'm new to working on low level code like u-boot. Something I don't > > understand is why things like the Ethernet address are stored in > > eeprom instead of flash. Is this something to do with how boards are > > manufactured? From a high level perspective it doesn't seem to matter > > if eeprom or flash is used. > > > I think you'll find varied implementations. > > For example, on the MPC8349EA-MDS-PB boards, the > MAC addresses are stored in U-Boot environment variables > and they're written on the CPU heatsink base. > > If you erase the Flash, then poof, gone are your MAC > addresses. When you Flash a new version of U-Boot you > need to set the IP addresses and save the environment > to the Flash. > > I would imagine some designers prefer saving these type > of parameters to an EEPROM, independent of the application > (bootloader, kernel, filesystem, etc) flash. This would > cut down on the support calls from customers who erase > their flash and forget their MAC addresses (or can't > see the MAC labels if the units are installed).
How are the MAC addresses assigned? So if I order ten Ethernet chips from Digikey will they come with something from the manufacturer indicating which MAC addresses to use? Or do I need to register as a vendor and get my own block of addresses? > So, as the designer, its up to you. But keep in mind that > you want to make it hard for a customer to screw up, so > a separate EEPROM could be a good choice. > > Cheers, > Dave > > -- Jon Smirl [EMAIL PROTECTED] ------------------------------------------------------------------------- This SF.net email is sponsored by: Microsoft Defy all challenges. Microsoft(R) Visual Studio 2008. http://clk.atdmt.com/MRT/go/vse0120000070mrt/direct/01/ _______________________________________________ U-Boot-Users mailing list [email protected] https://lists.sourceforge.net/lists/listinfo/u-boot-users
