Use the TIM4 peripheral to generate 1 ms time base using

TIM4 update interrupt

  ******************** (C)COPYRIGHT 2014 STMicroelectronics *******************
  * @file    TIM4/TIM4_TimeBase/readme.txt 
  * @author  MCD Application Team
  * @version V2.2.0
  * @date    30-September-2014
  * @brief   Description of the TIM4 Time Base Example.
  ******************************************************************************
  *
  * Licensed under MCD-ST Liberty SW License Agreement V2, (the "License");
  * You may not use this file except in compliance with the License.
  * You may obtain a copy of the License at:
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  *        http://www.st.com/software_license_agreement_liberty_v2
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  * distributed under the License is distributed on an "AS IS" BASIS, 
  * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
  * See the License for the specific language governing permissions and
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  ******************************************************************************
  

Example description

This example provides a short description of how to use the TIM4 peripheral to generate time base equal to 1 ms. In this example a "Delay" function is implemented based on the TIM4 time base. The four LEDs LD1..LD4 toggle with a timing defined by the Delay function.

The TIM4CLK frequency is 16MHz, the Prescaler is 128 so the TIM4 counter clock is 125 KHz. The TIM4 is running at TIM4 frequency = TIM4 counter clock / (TIM4_PERIOD + 1 = 125000 / 125 = 1 KHz. So the TIM4 generates an Update Interrupt each 1 / 1000 = 1 ms.

Directory contents

• TIM4\TIM4_TimeBase\main.c Main file containing the "main" function
• TIM4\TIM4_TimeBase\stm8s_conf.h Library Configuration file
• TIM4\TIM4_TimeBase\stm8s_it.c Interrupt routines source
• TIM4\TIM4_TimeBase\stm8s_it.h Interrupt routines declaration

Hardware and Software environment

• This example runs on STM8S and STM8A High density, Medium density devices and STM8S103x Low density devices.

• This example has been tested with STMicroelectronics STM8/128-EVAL evaluation board and can be easily tailored to any other development board.

• STM8/128-EVAL Set-up
  • Four leds LD1..LD4

How to use it ?

In order to make the program work, you must do the following :

• Copy all source files from this example folder to the template folder under Project
• Open your preferred toolchain
• Rebuild all files and load your image into target memory
• Run the example

Note:

• High-Density STM8A devices are the STM8AF52xx STM8AF6269/8x/Ax, STM8AF51xx, and STM8AF6169/7x/8x/9x/Ax microcontrollers where the Flash memory density ranges between 32 to 128 Kbytes
• Medium-Density STM8A devices are the STM8AF622x/4x, STM8AF6266/68, STM8AF612x/4x, and STM8AF6166/68 microcontrollers where the Flash memory density ranges between 8 to 32 Kbytes
• High-Density STM8S devices are the STM8S207xx, STM8S007 and STM8S208xx microcontrollers where the Flash memory density ranges between 32 to 128 Kbytes.
• Medium-Density STM8S devices are the STM8S105x and STM8S005 microcontrollers where the Flash memory density ranges between 16 to 32-Kbytes.
• Low-Density STM8S devices are the STM8S103xx, STM8S003 and STM8S903xx microcontrollers where the Flash density is 8 Kbytes.

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