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Travis
Sep 23rd, 2013, 08:06 PM
The backup clock fOFI generated internally is the default clock after start-up. It is used for bypassing the PLL for startup of the system without external clock. Furthermore it can be used as independent clock source for the watchdog module or even as system clock source during normal operation. While in prescaler mode this clock is automatically used as emergency clock if the external clock failure is detected.

harshan
Oct 17th, 2015, 12:28 AM
Hi,
I am working on XMC4100, i am trying to Configue the PLL with Internal Clock i.e., Fofi with Automatic Caliberation, as per datasheet the internal clock if automatic caliberation is taken then 24Mhz will be the clock,
trying to Configure the PLL to 2Mhz in normal mode with below information

Fpll = (N / (p * k2 ));
N = 80,
P = 12,
K2 = 80

but the clock is not configuring to 2Mhz, where might be the problem??

shenj
Oct 20th, 2015, 11:34 PM
Is there any application note about configuration of the clock system?

Travis
Oct 21st, 2015, 09:56 PM
Hi,
I am working on XMC4100, i am trying to Configue the PLL with Internal Clock i.e., Fofi with Automatic Caliberation, as per datasheet the internal clock if automatic caliberation is taken then 24Mhz will be the clock,
trying to Configure the PLL to 2Mhz in normal mode with below information

Fpll = (N / (p * k2 ));
N = 80,
P = 12,
K2 = 80

but the clock is not configuring to 2Mhz, where might be the problem??

Did you select the correct input clock source for the PLL?

harshan
Oct 23rd, 2015, 03:35 AM
Thanks for Reply,
Yes I Selected the PLL Clock Source as Fofi.