LPC MicrocontrollersのトピックRe: PLL source input other than IRC

PLL source input other than IRC

lpcware — Wed, 15 Jun 2016 22:57:00 GMT

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.

Re: PLL source input other than IRC

lpcware — Wed, 15 Jun 2016 22:57:01 GMT

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

Re: PLL source input other than IRC

lpcware — Wed, 15 Jun 2016 22:57:02 GMT

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

Re: PLL source input other than IRC

koonyook — Sun, 17 Jul 2016 12:10:42 GMT

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.

Re: PLL source input other than IRC

kerryzhou — Thu, 21 Jul 2016 10:30:08 GMT

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

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