PLL source input other than IRC

[lpcware]

Content originally posted in LPCWare by R D on Mon May 18 05:58:04 MST 2015

I'm trying to provide different clock source to PLL ie RTC,WDOSC,CLKIN but always end up in PLL configure error DEBUGOUT("PLL config error %d\r\n", pllError); error code is always 1 or 3. either pll request is low or pll ip is low.

any examples or light on this is appreciated.

[kerryzhou]

Hi LPC WARE,

     From the user manual, you can get that the PLL can choose :irc_clk, CLKIN, 32K_clk, if you don't want to use irc_clk, you can use CLKIN, 32_clk, and make sure it is in the PLL input clock range.

    About the sample code, you can refer to the LPC54102 LPCopen code:

LPCOpen Software for LPC5411X|NXP

Wish it helps you!

If you still have question, please let me know!

Have a great day,
Jjingjing

-----------------------------------------------------------------------------------------------------------------------
Note: If this post answers your question, please click the Correct Answer button. Thank you!

-----------------------------------------------------------------------------------------------------------------------

[koonyook]

I've fed RTC to PLL before on LPC54102.

When I set clock rate in board.h to 32768000 Hz, it works.

However, PLL will spend like 4 minutes to search for the right frequency and LOCK.

After that, the code works normally.

But 4 minutes is not practical, I'm looking into the solution.

[lpcware]

Content originally posted in LPCWare by R D on Mon May 18 06:35:12 MST 2015
LPCXpresso 54102

[lpcware]

Content originally posted in LPCWare by R2D2 on Mon May 18 06:16:16 MST 2015
Any hints about MCU?