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help regarding initialization of pll of lpc2129

i want to know how to use logic analyser to check the pllclock also i want to initialize the non-blocking pll i.e. it should not wait for the lock state please help me through this i m new to the arm 7 family

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  • Nothing says that you have to wait for the PLL to lock after having configured the PLL. You just have to make sure that the PLL has a stable frequency before you switch oscillator source.

    So - turn on the PLL and then continue with your program.

    At a later section in the program, check if the PLL has stabilized, and then start using it.

    It is, of curse, up to you to check how your program is affected by where/when you finally switch to the different frequency.

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  • Nothing says that you have to wait for the PLL to lock after having configured the PLL. You just have to make sure that the PLL has a stable frequency before you switch oscillator source.

    So - turn on the PLL and then continue with your program.

    At a later section in the program, check if the PLL has stabilized, and then start using it.

    It is, of curse, up to you to check how your program is affected by where/when you finally switch to the different frequency.

Children
  • alternatively a interrupt can be generated when the PLL locks, so that you can carry out other tasks while the PLL starts . once the PLL has locked as a stable clock source , it can replace the external clock source for Cclk.
    this is given in the hitex book for lpc2129 as an alternative way for starting the pll.

    also see datasheet for lpc2129 software interrupt register pin no. 12 i.e. for the same purpose