[U-Boot-Users] I2C Initialization

Wolfgang Denk
2003-03-05T08:15:05Z

In message <05ff01c2e2da$20817c60$6d4ba8c0@alb.sub.de> you wrote:
>
> In order to do that you need TWO general purpose I/O Lines. Its simple with
> the MPC8xx series, since the I2C Bus Pins can also be used as general
> purpose I/O lines. Can't you somehow directly control your I2C lines through
> the processor?

This is my hope...

> ((Note to myself: check whether the SOFT_I2C driver in u-boot does that kind
> of init, if NOT add it?))

This is exactly what I was thinking of. At least on 8xx and 82xx it
makes little sense to use the CPM based I2C anyway - the overhead
necessary to set up a transfer outperforms the win of speed for
almost all cases (except when loading the environment from big fast
devices like FRAM - but this again is only noticable when you are
optimizing for boot time, and then you will put the environment if
flash which is MUCH faster).

Best regards,

Wolfgang Denk

--
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