[U-Boot-Users] Any spport for Dallas 1-wire DS2502-E48

[Stefan Roese]

Hi Ed,

On Friday 28 July 2006 15:44, Edward Jubenville wrote:
> Has anyone tried to implement a 1-wire driver for Dallas/Maxim 1-Wire
> devices, in particular for a DS2502-E48 chip?

Please take a look at the file:

board/esd/cpci405/cpci405.c:

Here you will find an simple implementation to access to an 1-wire device. 
Search for ONE_WIRE_CLEAR...

> We are using a custom board based on the FreeScale Lite5200.  We have added
> a DS2502-E48 chip to give us a unique MAC address on each board, instead of
> having to buy/manage a block of MAC addresses from IEEE.
>
> I'm considering writing a standalone bit-banging application that u-boot
> can run to read and display the MAC address.  The user could then use the
> display for the "setenv ethaddr" command.  Would there be any way for the
> standalone program to modify the ethaddr environment variable directly?

Why not automatically set "ethaddr" to the value from the 1-wire device upon 
startup? This is done in other implementations already (not from 1-wire 
device though). For example:

board/tqm8xx/load_sernum_ethaddr.c

Best regards,
Stefan