[U-Boot-Users] mpc8xx RTC questions

[U-Boot-Users] mpc8xx RTC questions

[Sam Song]

Hi,

When setting "#define CONFIG_RTC_MPC8xx" ,how could I
do in my hardware scheme to make it really work?I mean
what kind of battery(Capacity and Type) and how to
connect it with 8xx?Someone said HW must monitor the
power status and before power failed SW could set 8xx
into powerdown mode for keeping 8xx RTC still work
with battery.Is this so?

Best regards,

Sam         

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[U-Boot-Users] mpc8xx RTC questions

[Wolfgang Denk]

In message <20040525011243.40738.qmail@web15212.mail.bjs.yahoo.com> you wrote:
> 
> When setting "#define CONFIG_RTC_MPC8xx" ,how could I
> do in my hardware scheme to make it really work?I mean
> what kind of battery(Capacity and Type) and how to
> connect it with 8xx?Someone said HW must monitor the

This is a hardware design question and far beyond the topics of  this
mailing  list.  I'm  pretty sure you can find some refernce design on
the Motorola web pages.

> power status and before power failed SW could set 8xx
> into powerdown mode for keeping 8xx RTC still work
> with battery.Is this so?

See the MPC8xx User's Manual, section "Clocks and Power Control".

Best regards,

Wolfgang Denk

-- 
Software Engineering:  Embedded and Realtime Systems,  Embedded Linux
Phone: (+49)-8142-4596-87  Fax: (+49)-8142-4596-88  Email: wd at denx.de
God grant me the senility to accept the things I cannot  change,  The
frustration  to  try to change things I cannot affect, and the wisdom
to tell the difference.

[U-Boot-Users] mpc8xx RTC questions

[Steven Scholz]

Wolfgang Denk wrote:
> In message <20040525011243.40738.qmail@web15212.mail.bjs.yahoo.com> you wrote:
> 
>>When setting "#define CONFIG_RTC_MPC8xx" ,how could I
>>do in my hardware scheme to make it really work?I mean
>>what kind of battery(Capacity and Type) and how to
>>connect it with 8xx?Someone said HW must monitor the
> 
> This is a hardware design question and far beyond the topics of  this
> mailing  list.  I'm  pretty sure you can find some refernce design on
> the Motorola web pages.

And BTW the RTC on MPC8xx draws much to much current! It's broken. See 
Errata for these proceossors.

Steven