readme.txt

STM32 的定时器控制实例程序！ 可以直接使用

/******************** (C) COPYRIGHT 2007 STMicroelectronics ********************
* File Name          : readme.txt
* Author             : MCD Application Team
* Version            : V1.0
* Date               : 10/08/2007
* Description        : Description of the TIM Example7.
********************************************************************************
* 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.
*******************************************************************************/
本例展示了如何使用外设TIM在定时器输入管脚接收到一个上升沿以后，产生一个单脉冲模式（One pulse Mode）的信号。

TIM2时钟设置为72MHz，预分频设置为1，TIM2计数器时钟可表达为：
TIM2 counter clock = TIMxCLK / (Prescaler +1) = 32 MHz。
设自动重载值（TIM2->ARR）为65535，因此可以触发TIM2的输入信号频率不应超过500Hz。

配置TIM2如下：
使用单脉冲模式，把外部输入信号连接到管脚TIM2 CH2 (PA.01)，设它的上升沿为触发沿，单脉冲信号从管脚TIM2_CH1 (PA.00)输出。

TIM_Pulse的值决定单脉冲时延的值，如下式这个值固定为455.08 us：
delay =  CCR1/TIM2 counter clock = 455.08 us

TIM_Period - TIM_Pulse的值决定单脉冲值，如下式这个值固定为1.365ms：
One Pulse value = (TIM_Period - TIM_Pulse)/TIM2 counter clock = 1.365 ms

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

This example shows how to use the TIM peripheral to generate a One pulse Mode 
after a Rising edge of an external signal is received in Timer Input pin.

The TIM2CLK frequency is set to 72 MHz, the Prescaler is 1 so the TIM2 counter
clock is 36 MHz. 
The Autoreload value is 65535 (TIM2->ARR), so the maximum frequency value to trigger 
the TIM2 input is 500 Hz.

The TIM2 is configured as the following: 
The One Pulse mode is used, the external signal is connected to TIM2 CH2 pin (PA.01), 
the Rising edge is used as active edge, the One Pulse signal is output 
on TIM2_CH1 (PA.00).

The TIM_Pulse defines the delay value, the delay value is fixed to 455.08 us:
delay =  CCR1/TIM2 counter clock = 455.08 us. 
The (TIM_Period - TIM_Pulse) defines the One Pulse value, the pulse value is fixed to 1.365ms:
One Pulse value = (TIM_Period - TIM_Pulse)/TIM2 counter clock = 1.365 ms.


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)
- Connect the TIM2_CH1 (PA.00) pin to an oscilloscope to show the waveform.
   
  
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******