8.6.4 PLL Reference Divider Select Register (PRDS) . . . . . . . . 106

8.7 Interrupts. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 107

8.8 Special Modes . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 107

8.8.1 Wait Mode . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 107

8.8.2 CGM During Break Interrupts . . . . . . . . . . . . . . . . . . . . . . 108

8.9 Acquisition/Lock Time Specifications . . . . . . . . . . . . . . . . . . . 108

8.9.1 Acquisition/Lock Time Definitions . . . . . . . . . . . . . . . . . . . 108

8.9.2 Parametric Influences on Reaction Time . . . . . . . . . . . . . 109

8.9.3 Choosing a Filter Capacitor. . . . . . . . . . . . . . . . . . . . . . . . 111

8.9.4 Reaction Time Calculation . . . . . . . . . . . . . . . . . . . . . . . . 111

8.2 Introduction

This section describes the clock generator module (CGM). 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, which is based on either the crystal clock divided by two or the phase-locked loop (PLL) clock, CGMPCLK, divided by two. This is the clock from which the SIM derives the system clocks, including the bus clock, which is at a frequency of CGMOUT/2. The PLL also generates a CGMVCLK clock, at 48MHz, for use as the USBCLK. The PLL is a fully functional frequency generator designed for use with crystals or ceramic resonators.

This CGM is optimized to generate a 48MHz reference frequency for the

USB module, from a 6MHz crystal.

Advance Information

MC68HC(7)08KH12 — Rev. 1.1

 

 

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Freescale Semiconductor

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MC68HC08KH12 specifications

The Freescale Semiconductor MC68HC08KH12 is a versatile microcontroller that has gained popularity in various embedded systems applications. Part of the HC08 family, this microcontroller combines a robust architecture with comprehensive on-chip features, making it suitable for a wide range of applications ranging from industrial control to consumer electronics.

One of the main features of the MC68HC08KH12 is its 8-bit architecture, which provides an optimal balance between performance and power efficiency. It operates at clock speeds of up to 2 MHz, allowing for efficient execution of instructions while maintaining low power consumption. The microcontroller is designed to operate over a voltage range of 2.7 to 5.5 volts, making it adaptable to various system requirements.

The MC68HC08KH12 is equipped with 1 Kbyte of RAM and 12 Kbytes of ROM, which allows for substantial program and data storage. The on-chip memory helps reduce the need for external components, simplifying the design of embedded systems and enhancing reliability. With a wide range of I/O options, including 26 general-purpose I/O pins, the microcontroller provides flexibility in interfacing with sensors, actuators, and other devices.

In terms of technologies, the MC68HC08KH12 features an advanced instruction set that enhances programming efficiency. It supports basic arithmetic operations, bit manipulation, and control transfer instructions, making it suitable for a variety of computational tasks. The integrated timers, analog-to-digital converters, and serial communication interfaces, including UART, provide the necessary tools for real-time control and data exchange with peripheral devices.

Another characteristic of the MC68HC08KH12 is its low power mode capabilities, which allow it to enter a sleep state during periods of inactivity. This feature is essential in battery-powered applications, where minimizing power consumption is crucial for extending operational life.

Overall, the Freescale Semiconductor MC68HC08KH12 stands out as a reliable microcontroller that combines performance, flexibility, and power efficiency. Its extensive features and technologies enable engineers to design robust embedded systems that meet the demands of modern applications. As a result, the MC68HC08KH12 remains a valuable choice for developers seeking a highly functional yet cost-effective microcontroller solution.
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