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Posts: 7
Registered: ‎04-16-2013

CP2114 external clock

Hello,

We are using an external clock that we feed in the CP2114, when setting SYSTEM_PROPS (byte 7) to 0x47, we see that the generated LRCLK is about 46kHz. The EXTCLK is at 49.152MHz. Also, I note that the LRCLK is not in sync with the EXTCLK. How to make all the clock signals in sync with the EXTCLK.
Posts: 7
Registered: ‎04-16-2013

Re: CP2114 external clock

Forget about this, I found the problem. It appears that when the correct config is taken on boot up, the signals are in sync with the EXTCLK. For some reasons, with the same configuration string and uploaded to RAM, the signals are not in sync.
Posts: 1
Registered: ‎10-08-2015

Re: CP2114 external clock

Hi i have a problem with the external clock. I am using a 49.152 MHz external, but no matter what i set byte 7 to, i cannot get 12.288 MHz MCLK. Only 12.000. A part from that working fine. I use WRITE TO RAM function in the setup tool.

 

How do i get 12.288 MHz?

 

Thanks

 

 

 

 

 

Posts: 1,971
Registered: ‎10-14-2014

Re: CP2114 external clock

Hi Dexadk,
Do you still have this issue? I guess you are using AN721 tool to configure the CP2114. What value are you trying for byte 7 (System_Props, datasheet page 32, table 23)?
Do you have a chance to try OTP writing rather than the RAM writing? As I remember but I am not sure now maybe the RAM write could not have effect on some clock.
Denver

WeiguoLu
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Posts: 348
Registered: ‎09-04-2013

Re: CP2114 external clock

[ Edited ]

Hello dexadk,

 

The clock configuration should be written to OTP, and the System frequency must be set to 49.152 MHz to to get 12.288 MHz MCLK output, because the MCLK is always the System Clock divided by 4.

 

Link below may help for you.

http://community.silabs.com/t5/Interface/Trouble-configuring-clocks-in-CP2114-cannot-get-12-288MHz-M...

 

Best regards,

Jiehui