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CDCE913 ClockPro tool v1.2.1 Reset PPM reference


My customer asked us following question about "Reset PPM refernce".

* When user pressed this button, could you tell us which registers are set ?

I think that variable of this GUI program is just cleared by pressing "Reset PPM reference".

(This means any registers were not set by pressing "Reset PPM reference".)

However, I do not have source code of this GUI, so I want you to confirm about this.

Best Regards,


  • Hi Machida,
    Your guess is right, there is no registers set upon clicking that button. only the reference for calculating the PPM error is taken from the already existing output frequencies, resulting in all ppm errors reset to zero. Initially the ppm calculation is done based on the desired frequency given in the wizard.
  • Hi Ahmed-san,

    Thank you for your reply.

    I understood.

    I'm sorry I have additional question.

    According to datasheet, "Enables 0-PPM Clock Generation" is described.

    I understand that this means that 0-PPM Clock Generation is automatically enabled. (User do NOT need to do specific setting to enable this function.)

    Is my understanding correct ?

    Best Regards,


  • Hello Machida-san,

    The phrase you mentioned found in the "features" section is merely talking about the chip capability rather than a specific function, and it has nothing to do with the GUI. it's not something that can be enabled/disabled. it's elaborated more in page 10 of the datasheet:

    "The deep M/N divider ratio allows the generation of zero-ppm audio/video, networking (WLAN, Bluetooth, Ethernet, GPS) or interface (USB, IEEE1394, memory stick) clocks from, for example, a 27-MHz reference input frequency."

    so the phrase means that the device has a high frequency VCO combined with deep divider which allows a wide range of synthesis, on top comes the VCXO capability which allows precise frequency adjustement for audio/video as described in detail in the datasheet.

    Best Regards,