mirror of
https://github.com/STMicroelectronics/STM32CubeF4.git
synced 2025-05-10 19:29:12 +08:00
112 lines
4.5 KiB
Plaintext
112 lines
4.5 KiB
Plaintext
/**
|
|
@page TIM_ExtTriggerSynchro TIM External Trigger Synchro example
|
|
|
|
@verbatim
|
|
******************** (C) COPYRIGHT 2017 STMicroelectronics *******************
|
|
* @file TIM/TIM_ExtTriggerSynchro/readme.txt
|
|
* @author MCD Application Team
|
|
* @brief Description of the TIM External Trigger Synchro example.
|
|
******************************************************************************
|
|
* @attention
|
|
*
|
|
* Copyright (c) 2017 STMicroelectronics.
|
|
* All rights reserved.
|
|
*
|
|
* This software is licensed under terms that can be found in the LICENSE file
|
|
* in the root directory of this software component.
|
|
* If no LICENSE file comes with this software, it is provided AS-IS.
|
|
*
|
|
******************************************************************************
|
|
@endverbatim
|
|
|
|
@par Example Description
|
|
|
|
This example shows how to synchronize TIM peripherals in cascade mode with an
|
|
external trigger.
|
|
In this example three timers are used:
|
|
|
|
1/TIM1 is configured as Master Timer:
|
|
- Toggle Mode is used
|
|
- The TIM1 Enable event is used as Trigger Output
|
|
|
|
2/TIM1 is configured as Slave Timer for an external Trigger connected to TIM1
|
|
TI2 pin (TIM1 CH2 configured as input pin):
|
|
- The TIM1 TI2FP2 is used as Trigger Input
|
|
- Rising edge is used to start and stop the TIM1: Gated Mode.
|
|
|
|
3/TIM3 is slave for TIM1 and Master for TIM4,
|
|
- Toggle Mode is used
|
|
- The ITR1(TIM1) is used as input trigger
|
|
- Gated mode is used, so start and stop of slave counter
|
|
are controlled by the Master trigger output signal(TIM1 enable event).
|
|
- The TIM3 enable event is used as Trigger Output.
|
|
|
|
4/TIM4 is slave for TIM3,
|
|
- Toggle Mode is used
|
|
- The ITR2(TIM3) is used as input trigger
|
|
- Gated mode is used, so start and stop of slave counter
|
|
are controlled by the Master trigger output signal(TIM3 enable event).
|
|
|
|
The TIM1CLK is fixed to 180 MHZ, the Prescaler is equal to 5 so the TIMx clock
|
|
counter is equal to 30 MHz.
|
|
The TIM3CLK and TIM4CLK are fixed to 90 MHZ, the Prescaler is equal to 5
|
|
so the TIMx clock counter is equal to 15 MHz.
|
|
The Three Timers are running at:
|
|
TIMx frequency = TIMx clock counter/ 2*(TIMx_Period + 1) = 100 KHz.
|
|
|
|
The starts and stops of the TIM1 counters are controlled by the external trigger.
|
|
The TIM3 starts and stops are controlled by the TIM1, and the TIM4 starts and
|
|
stops are controlled by the TIM3.
|
|
|
|
|
|
@note Care must be taken when using HAL_Delay(), this function provides accurate delay (in milliseconds)
|
|
based on variable incremented in SysTick ISR. This implies that if HAL_Delay() is called from
|
|
a peripheral ISR process, then the SysTick interrupt must have higher priority (numerically lower)
|
|
than the peripheral interrupt. Otherwise the caller ISR process will be blocked.
|
|
To change the SysTick interrupt priority you have to use HAL_NVIC_SetPriority() function.
|
|
|
|
@note The application needs to ensure that the SysTick time base is always set to 1 millisecond
|
|
to have correct HAL operation.
|
|
|
|
@par Keywords
|
|
|
|
Timers, PWM, External Trigger, Synchronization, Cascade mode, Master, Slave, Duty Cycle, Waveform,
|
|
Oscilloscope, Output, Signal
|
|
|
|
@par Directory contents
|
|
|
|
- TIM/TIM_ExtTriggerSynchro/Inc/stm32f4xx_hal_conf.h HAL configuration file
|
|
- TIM/TIM_ExtTriggerSynchro/Inc/stm32f4xx_it.h Interrupt handlers header file
|
|
- TIM/TIM_ExtTriggerSynchro/Inc/main.h Main program header file
|
|
- TIM/TIM_ExtTriggerSynchro/Src/stm32f4xx_it.c Interrupt handlers
|
|
- TIM/TIM_ExtTriggerSynchro/Src/main.c Main program
|
|
- TIM/TIM_ExtTriggerSynchro/Src/stm32f4xx_hal_msp.c HAL MSP module
|
|
- TIM/TIM_ExtTriggerSynchro/Src/system_stm32f4xx.c STM32F4xx system clock configuration file
|
|
|
|
|
|
@par Hardware and Software environment
|
|
|
|
- This example runs on STM32F429xx/STM32F439xx devices.
|
|
|
|
- This example has been tested with STMicroelectronics STM324x9I-EVAL RevB
|
|
evaluation boards and can be easily tailored to any other supported device and development board
|
|
|
|
- STM324x9I-EVAL RevB Set-up
|
|
- Connect an external trigger to the TIM1 CH2 (PE.11).
|
|
|
|
- Connect the following pins to an oscilloscope to monitor the different waveforms:
|
|
- TIM1 CH1 (PA.08)
|
|
- TIM3 CH1 (PC.06)
|
|
- TIM4 CH1 (PB.06)
|
|
|
|
|
|
@par How to use it ?
|
|
|
|
In order to make the program work, you must do the following :
|
|
- Open your preferred toolchain
|
|
- Rebuild all files and load your image into target memory
|
|
- Run the example
|
|
|
|
|
|
*/
|