发布时间:2024-06-27 18:01
源码下载地址:http://download.csdn.net/detail/dazhou158/5253187
main.c
stm32f4xx_it.c
ReadMe.txt
/**
@page TIM_TimeBase TIM_TimeBase
@verbatim
******************************************************************************
* @file TIM_TimeBase/readme.txt
* @author MCD Application Team
* @version V1.0.0
* @date 19-September-2011
* @brief Description of the TIM Time Base example.
******************************************************************************
* THE PRESENT FIRMWARE 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 FIRMWARE AND/OR THE USE MADE BY CUSTOMERS OF THE
* CODING INFORMATION CONTAINED HEREIN IN CONNECTION WITH THEIR PRODUCTS.
******************************************************************************
@endverbatim
@par 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 TIM3CLK frequency is set to SystemCoreClock / 2 (Hz), to get TIM3 counter
clock at 500 KHz so the Prescaler is computed as following:
- Prescaler = (TIM3CLK / TIM3 counter clock) - 1
SystemCoreClock is set to 168 MHz for STM32F4xx Devices Revision A.
The TIM3 CC1 register value is equal to 54618,
CC1 update rate = TIM3 counter clock / CCR1_Val = 9.154 Hz,
so the TIM3 Channel 1 generates an interrupt each 109.2ms
The TIM3 CC2 register is equal to 27309,
CC2 update rate = TIM3 counter clock / CCR2_Val = 18.31 Hz
so the TIM3 Channel 2 generates an interrupt each 54.6ms
The TIM3 CC3 register is equal to 13654,
CC3 update rate = TIM3 counter clock / CCR3_Val = 36.62 Hz
so the TIM3 Channel 3 generates an interrupt each 27.3ms
The TIM3 CC4 register is equal to 6826,
CC4 update rate = TIM3 counter clock / CCR4_Val = 73.25 Hz
so the TIM3 Channel 4 generates an interrupt each 13.65ms.
When the counter value reaches the Output compare registers values, the Output
Compare interrupts are generated and, in the handler routine, 4 pins(PD.12, PD.13,
PD.14 and PD.15) are toggled with the following frequencies:
//引脚输出的频率
- PD.12: 4.57 Hz (CC1)
- PD.13: 9.15 Hz (CC2)
- PD.14: 18.31 Hz (CC3)
- PD.15: 36.62 Hz (CC4)
@par Directory contents
- TIM_TimeBase/stm32f4xx_conf.h Library Configuration file
- TIM_TimeBase/stm32f4xx_it.c Interrupt handlers
- TIM_TimeBase/stm32f4xx_it.h Interrupt handlers header file
- TIM_TimeBase/main.c Main program
- TIM_TimeBase/system_stm32f4xx.c STM32F4xx system clock configuration file
@par Hardware and Software environment
- This example runs on STM32F4xx Devices Revision A.
- This example has been tested with STM32F4-Discovery (MB997) RevA and can be
easily tailored to any other development board.
- STM32F4-Discovery
- Use LED4, LED3, LED5 and LED6 connected respectively to PD.12, PD.13,D.14
and PD.15 pins and connect them on an oscilloscope to show the different
Time Base signals.
@par How to use it ?
In order to make the program work, you must do the following :
+ EWARM
- Open the TIM_TimeBase.eww workspace
- Rebuild all files: Project->Rebuild all
- Load project image: Project->Debug
- Run program: Debug->Go(F5)
+ MDK-ARM
- Open the TIM_TimeBase.uvproj project
- Rebuild all files: Project->Rebuild all target files
- Load project image: Debug->Start/Stop Debug Session
- Run program: Debug->Run (F5)
+ TASKING
- Open TASKING toolchain.
- Click on File->Import, select General->'Existing Projects into Workspace'
and then click "Next".
- Browse to TASKING workspace directory and select the project "TIM_TimeBase"
- Rebuild all project files: Select the project in the "Project explorer"
window then click on Project->build project menu.
- Run program: Select the project in the "Project explorer" window then click
Run->Debug (F11)
+ TrueSTUDIO
- Open the TrueSTUDIO toolchain.
- Click on File->Switch Workspace->Other and browse to TrueSTUDIO workspace
directory.
- Click on File->Import, select General->'Existing Projects into Workspace'
and then click "Next".
- Browse to the TrueSTUDIO workspace directory and select the project "TIM_TimeBase"
- Rebuild all project files: Select the project in the "Project explorer"
window then click on Project->build project menu.
- Run program: Select the project in the "Project explorer" window then click
Run->Debug (F11)
*