Am Mittwoch, 4. Dezember 2002 12:43 schrieb Wolfgang Denk:
In message 0212041158460F.06014@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