mc68hc908sr12 Freescale Semiconductor, Inc, mc68hc908sr12 Datasheet - Page 113

• Manufacturer Part Number: mc68hc908sr12
• Description: M68hc08 Microcontrollers Microcontroller
• Manufacturer: Freescale Semiconductor, Inc

8.3 Features
8.4 Functional Description
MC68HC908SR12•MC68HC08SR12 — Rev. 5.0
Freescale Semiconductor
Features of the CGM include:
The CGM consists of three major sub-modules:
Figure 8-1
Figure 8-2
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Phase-locked loop with output frequency in integer multiples of an
integer dividend of the crystal reference
Low-frequency crystal operation with low-power operation and
high-output frequency resolution
Programmable prescaler for power-of-two increases in frequency
Programmable hardware voltage-controlled oscillator (VCO) for
low-jitter operation
Automatic bandwidth control mode for low-jitter operation
Automatic frequency lock detector
CPU interrupt on entry or exit from locked condition
Configuration register bit to allow oscillator operation during stop
mode
Oscillator module — The oscillator module generates the constant
reference frequency clock, CGMRCLK (buffered CGMXCLK).
Phase-locked loop (PLL) — The PLL generates the
programmable VCO frequency clock, CGMVCLK, and the divided,
CGMPCLK. The CGMVCLK provides the input reference clock to
the PWM and analog modules.
Base clock selector circuit — This software-controlled circuit
selects either CGMXCLK divided by two or the divided VCO clock,
CGMPCLK, divided by two as the base clock, CGMOUT. The SIM
derives the system clocks from either CGMOUT or CGMXCLK.
Clock Generator Module (CGM)
shows the structure of the CGM.
is a summary of the CGM registers.
Clock Generator Module (CGM)
Data Sheet
Features
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