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NUC970 Technical Reference Manual
Publication Release Date: Dec. 15, 2015
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Revision V1.30
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Clock Controller (CLK_CTL)
5.3
5.3.1 Overview
The clock controller generates all clocks for Video, Audio, CPU, system bus and all functionalities.
This chip includes two PLL modules. The clock source for each functionality comes from the PLL, or
from the external crystal input directly. For each clock there is a bit on the CLKEN register to control
the clock ON or OFF individually, and the divider setting is in the CLK_DIVCTL register. The register
can also be used to control the clock enable or disable for power control.
5.3.2 Features
Supports two PLLs, up to 500 MHz, for high performance system operation
External 12 MHz high speed crystal input for precise timing operation
External 32.768 kHz low speed crystal input for RTC function and low speed clock source