Information

Section number Title Page
24.4 Functional description...................................................................................................................................................520
24.4.1 MCG mode state diagram............................................................................................................................520
24.4.2 Low Power Bit Usage..................................................................................................................................525
24.4.3 MCG Internal Reference Clocks..................................................................................................................525
24.4.4 External Reference Clock............................................................................................................................525
24.4.5 MCG Fixed frequency clock .......................................................................................................................526
24.4.6 MCG PLL clock ..........................................................................................................................................526
24.4.7 MCG Auto TRIM (ATM)............................................................................................................................527
24.5 Initialization / Application information........................................................................................................................528
24.5.1 MCG module initialization sequence...........................................................................................................528
24.5.2 Using a 32.768 kHz reference......................................................................................................................530
24.5.3 MCG mode switching..................................................................................................................................531
Chapter 25
Oscillator (OSC)
25.1 Introduction...................................................................................................................................................................541
25.2 Features and Modes......................................................................................................................................................541
25.3 Block Diagram..............................................................................................................................................................542
25.4 OSC Signal Descriptions..............................................................................................................................................542
25.5 External Crystal / Resonator Connections....................................................................................................................543
25.6 External Clock Connections.........................................................................................................................................544
25.7 Memory Map/Register Definitions...............................................................................................................................545
25.7.1 OSC Memory Map/Register Definition.......................................................................................................545
25.8 Functional Description..................................................................................................................................................546
25.8.1 OSC Module States......................................................................................................................................546
25.8.2 OSC Module Modes.....................................................................................................................................548
25.8.3 Counter.........................................................................................................................................................550
25.8.4 Reference Clock Pin Requirements.............................................................................................................550
25.9 Reset..............................................................................................................................................................................550
25.10 Low Power Modes Operation.......................................................................................................................................551
K20 Sub-Family Reference Manual, Rev. 1.1, Dec 2012
20
Preliminary
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