S3C8245/P8245/C8249/P8249 CLOCK CIRCUIT
7-1
7CLOCK CIRCUIT
OVERVIEW
The clock frequency generated for the S3C8245/C8249 by an external crystal can range from 1 MHz to 10 MHz. The
maximum CPU clock frequency is 10 MHz. The XIN and XOUT pins connect the external oscillator or clock source to
the on-chip clock circuit.
SYSTEM CLOCK CIRCUIT
The system clock circuit has the following components:
—External crystal or ceramic resonator oscillation source (or an external clock source)
—Oscillator stop and wake-up functions
—Programmable frequency divider for the CPU clock (fxx divided by 1, 2, 8, or 16)
—System clock control register, CLKCON
—Oscillator control register, OSCCON and STOP control register, STPCON
X
IN
X
OUT
C1
C2
S3C8245/C8249
Figure 7-1. Main Oscillator Circuit
(Crystal or Ceramic Oscillator)
X
IN
X
OUT
S3C8245/C8249
Figure 7-2. Main Oscillator Circuit
(RC Oscillator)