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CDCI6214: How to access registers (EEPROMSEL=High)

Prodigy 65 points

Replies: 3

Views: 80

Part Number: CDCI6214

Hi team

the configuration of our device is:

  • EEPROMSEL = High
  • mode = 0h (enable I2C)

we confirmed that an arbitrary frequency was output, by writing to the EEPROM with I2C and restart the device. 

But we want to rewrite the register to change the output frequency while driving the device.

Can we dynamically change the output frequency with I2C interface (in Operational Mode) ?

Can we not access register in Operational Mode? Only Fall-Back mode?

best regards


  • Hello Kota,

    You can dynamically change the output frequency through I2C interface in all modes of operation, as long as the mode bit = 0.

    If you'd like to use I2C to write into the device every time it powers up, you can use the fall-back mode - it disables loading the NVM contents at power-up.

    Best regards,


  • In reply to Dinesh Jain:

    Hello dinesh,

    Thanks for the response

    When we rewrite registers, do we have to access 0x74(REFSEL=EEPROMSEL=MID)?

    Can I rewrite the register at slave address 0x77(EEPROMSEL=High)?

    Does the output frequency change without PoR?

    If possible, please tell me the procedure.


  • In reply to Kota:

    Hello Kota,

    For REFSEL=EEPROMSEL=MID, I2C Address would be 0x74.

    For RESEL=L or H, EEPROMSEL=L or H, I2C Address can be 0x76 or 0x77 (depending upon I2C_A0 bit).

    If you change the PLL settings through I2C, please click on Recal button (if you are using TICS Pro) or write into recal bit to recalibrate the PLL.

    Any changes to settings of Reference Input & Output Clock should be immediate.

    There is no need for POR.