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 Example5.
********************************************************************************
* 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.
*******************************************************************************/
本例展示了如何设置TIM工作在输出比较-时间模式（Output Compare Timing mode），产生相应的中断，以在不同通道上产生不同的时间基数。

TIM2时钟设置为36MHz，预分频设置为4，TIM2计数器时钟可表达为：
TIM2 counter clock = TIMxCLK / (Prescaler +1) = 7.2 MHz
设置TIM2_CCR1寄存器值为49152，则CC1更新频率为TIM2计数器时钟频率（7.2 MHz）除以CCR1寄存器值(49152)，为146.48 Hz。因此，TIM2通道1每6.8ms产生一个中断。
同理，根据寄存器TIM2_CCR2 、TIM2_CCR3和 TIM2_CCR4的值，TIM2通道2每4.55ms产生一个中断；TIM2通道3每2.27ms产生一个中断；TIM2通道4每1.13ms产生一个中断。
当计数器的值达到出数比较寄存器（Output compare register即TIMx_CCRx）的值时，产生输出比较中断（Output Compare interrupt），在中断历程中，按以下频率翻转输出管脚PC.06 – PC.09的状态：
- PC.06: 73.24Hz (CC1 通道1)
- PC.07: 109.8Hz (CC2通道2)
- PC.08: 219.7Hz (CC3通道3) 
- PC.09: 439.4Hz (CC4通道4) 

在STM3210B-LK1上，应当改PC.06 – PC.09为PC.04 – PC.07。与它们相连的LED会以不同的频率闪耀，不过，由于频率相对高了，肉眼是观察不出区别的。

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

This example shows how to configure the TIM peripheral in Output Compare Timing 
mode with the corresponding Interrupt requests for each channel in order to generate
4 different time bases.

The TIMxCLK frequency is set to 36 MHz, the Prescaler is 4 so the TIM2 counter
clock is 7.2 MHz. 

The TIM2 CC1 register value is equal to 49152, 
CC1 update rate = TIM2 counter clock / CCR1_Val = 146.48 Hz,
so the TIM2 Channel 1 generates an interrupt each 6.8ms

The TIM2 CC2 register is equal to 32768, 
CC2 update rate = TIM2 counter clock / CCR2_Val = 219.7 HzHz
so the TIM2 Channel 2 generates an interrupt each 4.55ms

The TIM2 CC3 register is equal to 16384, 
CC3 update rate = TIM2 counter clock / CCR3_Val = 439.4Hz
so the TIM2 Channel 3 generates an interrupt each 2.27ms

The TIM2 CC4 register is equal to 8192, 
CC4 update rate = TIM2 counter clock / CCR4_Val =  878.9 Hz
so the TIM2 Channel 4 generates an interrupt each 1.13ms.


When the counter value reaches the Output compare registers values, the Output 
Compare interrupts are generated and, in the handler routine, 4 pins(PC.06, PC.07,
PC.08 and  PC.09) are toggled with the following frequencies: 

- PC.06: 73.24Hz (CC1)
- PC.07: 109.8Hz (CC2)
- PC.08: 219.7Hz (CC3) 
- PC.09: 439.4Hz (CC4)


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 an oscilloscope on PC.06, PC.07, PC.08 and  PC.09 to show the different
Time Base signals.
  
  
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******