September 2008

Rev 2

1/8

AN2669

Application note

How to configure the STM8A microcontroller clocks

Introduction

The STM8A microcontroller has a very flexible clock controller (CLK) that allows the clocks

to be reconfigured at any time to suit different requirements or functional modes in the

application.

There are four clock sources that can be used.

This application note provides practical examples of how to program the STM8A CLK

registers. The source code of the examples is included in the STM8 firmware library.

For further information and a hardware description of the STM8A CLK, please refer to the

section on ‘Clock control (CLK)’ in the STM8A microcontroller family reference manual

(RM0009). Please contact STMicroelectronics for information on the STM8 firmware library.

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