MC68HC08AZ60ACFU MOTOROLA [Motorola, Inc], MC68HC08AZ60ACFU Datasheet - Page 140

• Manufacturer Part Number: MC68HC08AZ60ACFU
• Description: Microcontrollers
• Manufacturer: MOTOROLA [Motorola, Inc]

Clock Generator Module (CGM)
9.2 Introduction
9.3 Features
Advance Information
140
9.8.1
9.8.2
9.9
9.10
9.10.1
9.10.2
9.10.3
9.10.4
The CGM generates the crystal clock signal, CGMXCLK, which operates
at the frequency of the crystal. The CGM also generates the base clock
signal, CGMOUT, from which the system clocks are derived. CGMOUT
is based on either the crystal clock divided by two or the phase-locked
loop (PLL) clock, CGMVCLK, divided by two. The PLL is a frequency
generator designed for use with 1-MHz to 16-MHz crystals or ceramic
resonators. The PLL can generate an 8-MHz bus frequency without
using high frequency crystals.
Features of the CGM include:
•
•
•
•
•
Phase-Locked Loop with Output Frequency in Integer Multiples of
the Crystal Reference
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
CGM During Break Interrupts . . . . . . . . . . . . . . . . . . . . . . . 160
Acquisition/Lock Time Specifications . . . . . . . . . . . . . . . . 160
Wait Mode . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 159
Stop Mode . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 160
Acquisition/Lock Time Definitions . . . . . . . . . . . . . . . . . 160
Parametric Influences on Reaction Time . . . . . . . . . . . . 162
Choosing a Filter Capacitor . . . . . . . . . . . . . . . . . . . . . . 163
Reaction Time Calculation . . . . . . . . . . . . . . . . . . . . . . . 163
Clock Generator Module (CGM)
MC68HC08AZ60A — Rev 0.0
MOTOROLA