[U-Boot-Users] i.MX31: question about CFG_HZ and CKIL
Jens Gehrlein
sew_s at tqs.de
Wed May 7 10:59:31 CEST 2008
Hi all,
in the i.MX31 processor reference manual they mention a 32 kHz clock as
input for several timers and controllers. Sometimes it's called
ipg_clk_32k. But the documentation does not clearly state, that this
clock actually is the CKIL.
As far as I could derive from the ADS schematics the CKIL is feeded with
32768 Hz instead of 32000 Hz. On our board we use 32768 Hz either.
If CKIL is the above mentioned 32 kHz clock, the resulting deviation in
the timers is "only" about 2.4% as long as CFG_HZ in mx31ads.h is 32000
Hz. Although it works with the current definition, I'd like to know your
opinions, whether it is necessary to adjust this value.
Thank you for comments.
Best Regards,
Jens
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