Samsung S3C9228/P9228 사용자 설명서
S3C9228/P9228
CLOCK CIRCUITS
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CLOCK CIRCUITS
OVERVIEW
The S3C9228 microcontroller has two oscillator circuits: a main clock, and a sub clock circuit. The CPU and
peripheral hardware operate on the system clock frequency supplied through these circuits. The maximum CPU
clock frequency, is determined by CLKCON register settings.
peripheral hardware operate on the system clock frequency supplied through these circuits. The maximum CPU
clock frequency, is determined by CLKCON register settings.
SYSTEM CLOCK CIRCUIT
The system clock circuit has the following components:
— Crystal, ceramic resonator, RC oscillation source (main clock only), or an external clock
— Oscillator stop and wake-up functions
— Programmable frequency divider for the CPU clock (fxx divided by 1, 2, 8, or 16)
— Clock circuit control register, CLKCON
— Oscillator control register, OSCCON
CPU CLOCK NOTATION
In this document, the following notation is used for descriptions of the CPU clock:
fx
main clock
fxt sub clock
fxx selected system clock