Re: [ECOS] Frequency scaling on iPaq

[Cristiano Ligieri Pereira <cpereira at ics dot uci dot edu>]

have you tried it on eCos? I'm doing exacly the same things that are done
in the change_clock_speed() function execpt the function call to
recalibrate_delay(void) since it deals with linux global variables.

Now the system frezzes and the LCD display shows nothing when I try to    
scale lower than 162Mhz. Should I calibrate the FLASH timings as 
well? Although it's not done in the linux source code.

Thanks,
Cristiano.


------------------------------------------------------------
Cristiano Ligieri Pereira - http://www.ics.uci.edu/~cpereira

On Tue, 5 Jun 2001, Nicolas Pitre wrote:
> 
> We had that problem under Linux and the solution you described is correct.
> Look at the Linux code for reference.  It works fine on iPAQ.
> 
> Note that changing the PLL must be done  for long term power saving.  Since
> the PLL requires quite a delay to stabilize when it is changed you can't use
> CPU speed reduction for things like the idle loop.
> 
> 
> Nicolas
> 
>