readme.txt

新型的M3核ARM开发例程

/******************** (C) COPYRIGHT 2007 STMicroelectronics ********************
* File Name          : readme.txt
* Author             : MCD Application Team
* Date First Issued  : 05/21/2007
* Description        : Description of the TIM Example6.
********************************************************************************
* History:
* 05/21/2007: V0.3
********************************************************************************
* THE PRESENT SOFTWARE WHICH IS FOR GUIDANCE ONLY AIMS AT PROVIDING CUSTOMERS
* WITH CODING INFORMATION REGARDING THEIR PRODUCTS IN ORDER FOR THEM TO SAVE TIME.
* AS A RESULT, STMICROELECTRONICS SHALL NOT BE HELD LIABLE FOR ANY DIRECT,
* INDIRECT OR CONSEQUENTIAL DAMAGES WITH RESPECT TO ANY CLAIMS ARISING FROM THE
* CONTENT OF SUCH SOFTWARE AND/OR THE USE MADE BY CUSTOMERS OF THE CODING
* INFORMATION CONTAINED HEREIN IN CONNECTION WITH THEIR PRODUCTS.
*******************************************************************************/

Example description
===================

This example shows how to use the TIM peripheral to measure the frequency and 
duty cycle of an external signal.

The TIMxCLK frequency is set to 72 MHz, the Prescaler is 0x0 so the TIM2 counter 
clock is 72 MHz. so the minimum frequency value to measure is 1100 Hz.
TIM2 is configured in PWM Input Mode: the external signal is connected to 
TIM2 Channel2 used as input pin.
To measure the frequency and the duty cycle we use the TIM2 CC2 interrupt request,
so In the TIM2_IRQHandler routine, the frequency and the duty cycle of the external 
signal are computed. 
The "Frequency" variable contains the external signal frequency:
Frequency = TIM2 counter clock / TIM2_CCR2 in Hz, 
The "Duty_Cycle" variable contains the external signal duty cycle:
Duty_Cycle = (TIM2_CCR1*100)/(TIM2_CCR2) in %.


Directory contents
==================
stm32F10x_conf.h  Library Configuration file
stm32F10x_it.c    Interrupt handlers
stm32F10x_it.h    Interrupt handlers header file
main.c            Main program
 

Hardware environment
====================
Connect the external signal to measure to the TIM2 CH2 pin (PA.01)
   
  
How to use it
=============
In order to make the program work, you must do the following:
- Create a project and setup all your toolchain's start-up files
- Compile the directory content files and required Library files:
  + stm32F10x_lib.c
  + stm32F10x_tim.c
  + stm32F10x_gpio.c
  + stm32F10x_rcc.c
  + stm32F10x_nvic.c
  + stm32F10x_flash.c

- Link all compiled files and load your image into either RAM or Flash
- Run the example


******************* (C) COPYRIGHT 2007 STMicroelectronics *****END OF FILE******