[U-Boot-Users] External RTC in MPC860P (i2c - rtc DS1307)

[Wolfgang Denk]

In message <20060510122158.47635.qmail at web36907.mail.mud.yahoo.com> you wrote:
> 
> We are interfacing external RTC DS1307 in MPC860P(40MHz core frequency).
> I've configured the following files in U-boot-1.1.3.

Why are you using old code?

> 1.    In i2c.c

You should never have to modify this file.

> #define    CFG_I2C_SLAVE         0xFE
...
> 2.    In  include/configs/BOARD.h
...
> #define    CFG_I2C_SLAVE         0x7F

SO what is your slave address? 0xFE or 0x7F ?

> #define    CONFIG_HARD_I2C       1

Makes not much sense to me. I prefer to use soft-I2C.

> 3.    In <board/board.h>
...
> #define    CONFIG_HARD_I2C       1
> #define    CFG_I2C_SPEED        50000
> #define    CFG_I2C_SLAVE         0xFE

And yet another set of definitions?

Do NOT do this.

> Is the above things correct in order to get the date and time
> up and running in an MPC860P based custom board.

No, this is NOT correct. You must  not  define  the  same  things  in
several place, and differently. Use a single definition in your board
config file, and make sure it is correct.


Best regards,

Wolfgang Denk

-- 
Software Engineering:  Embedded and Realtime Systems,  Embedded Linux
Phone: (+49)-8142-66989-10 Fax: (+49)-8142-66989-80 Email: wd at denx.de
Ill-chosen abstraction is particularly evident in the design  of  the
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