[U-Boot-Users] I2C address above 0x7f

[Stephan Linz]

Am Mittwoch,  4. Dezember 2002 12:43 schrieb Wolfgang Denk:
> In message <0212041158460F.06014 at pcj86.jena.mazet.de> you wrote:
> > currently I play with the I2C facility of PPCBoot 2.0.0 (I know, it's
> > deprecated). At my TQ850L I'm using the I2C hardware machine
> > (CONFIG_HARD_I2C) with needed configuration:
> >
> >    * CFG_I2C_SPEED=400000
> >    * CFG_I2C_SLAVE=0x7f
>
> Why don't you use the default of 0xFE?

Oh yes, the value above was coming from TQM8260.h. I've changed.

>
> > Hm, what's the meaning of CFG_I2C_SLAVE ? I've expected it's the highes
> > valid slave address, isn't it ?
>
> No, what makes you think so? It's the value that gets programmed into
> the MPC8xx I2C controller's I2ADD register. See the Users Manual  for
> details.
>
>
> The subject suggests you ntended to ask something different?

Oops, I've forgot to ask. Now, at my TQ there is a so named FRAM I2C brick 
connected to I2CSDA (PB27) and I2CSCL (PB26). The FRAM has two different 
addresses both above 0x7F, 0xAE for write access and 0xAF for read access. 
The FRAM is similar to E2PROM bricks like AT24C64.

My question: Is there an read/write abstraction layer inside of the I2C stuff 
of PPCBoot ? I don't know if I should use the bit shifted address 0x57 
instead of 0xAE for calling imd -- I think 0x57. However, upt to now I've 
tried both addresses without success.

Ah, just now I see there is a nice tool to scan I2C devices (iprobe). Can 
anybody give me an generic command line dump with iprobe in action? I've ran 
iprobe but without any success. The only thing I see is:

=> iprobe
Valid chip addresses:
=> _

I think iprobe has not found any valid chip. Is it so ?

>
> Best regards,
>
> Wolfgang Denk

-- 

======================================================================
Stephan Linz
Software Engineer

MAZeT GmbH                   Email:   mailto:linz at mazet.de
Branche office Jena          Phone:   +49-3641-2809-55
Göschwitzer Straße 32        Fax  :   +49-3641-2809-12
D-07745 JENA
Germany

Visit our web-pages: http://www.MAZeT.de
======================================================================