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/**
@page TIM_OnePulse TIM One Pulse example
@verbatim
******************************************************************************
* @file TIM/TIM_OnePulse/readme.txt
* @author MCD Application Team
* @brief Description of the TIM One Pulse example.
******************************************************************************
*
* Copyright (c) 2019-2021 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
Use of the TIM peripheral to generate a single pulse when
an external signal rising edge is received on the timer input pin.
Clock setup for TIM2
================================
TIM2CLK = SystemCoreClock = 64 MHz.
Prescaler = (TIM2CLK /TIM2 counter clock) - 1
The prescaler value is computed in order to have TIM2 counter clock
set at 1000000 Hz.
The Autoreload value is 65535 (TIM2->ARR), so the maximum frequency value to
trigger the TIM2 input is 1000000/65535 [Hz].
Configuration of TIM2 in One Pulse Mode
===================================================
- The external signal is connected to TIM2_CH2 pin (PA.01),
and a rising edge on this input is used to trigger the Timer.
- The One Pulse signal is output on TIM2_CH1 (PA.00).
The delay value is fixed to:
- Delay = CCR1/TIM2 counter clock
= 16383 / 1000000 [sec]
The pulse value is fixed to :
- Pulse value = (TIM_Period - TIM_Pulse)/TIM2 counter clock
= (65535 - 16383) / 1000000 [sec]
The one pulse waveform can be displayed using an oscilloscope and it looks
like this.
____
| |
CH2 _________________________| |__________________________________________
___________________________
| |
CH1 ______________________________________| |_____
<---Delay----><------Pulse--------------->
@par Keywords
Timer, Output, signals, One Pulse, PWM, Oscilloscope, External signal, Autoreload, Waveform
@par Directory contents
- TIM/TIM_OnePulse/Inc/stm32wbxx_hal_conf.h HAL configuration file
- TIM/TIM_OnePulse/Inc/stm32wbxx_it.h Interrupt handlers header file
- TIM/TIM_OnePulse/Inc/main.h Header for main.c module
- TIM/TIM_OnePulse/Src/stm32wbxx_it.c Interrupt handlers
- TIM/TIM_OnePulse/Src/main.c Main program
- TIM/TIM_OnePulse/Src/stm32wbxx_hal_msp.c HAL MSP file
- TIM/TIM_OnePulse/Src/system_stm32wbxx.c STM32WBxx system source file
@par Hardware and Software environment
- This example runs on STM32WB55xx devices.
- In this example, the clock is set to 64 MHz.
- This example has been tested with P-NUCLEO-WB55 board and can be
easily tailored to any other supported device and development board.
- P-NUCLEO-WB55 Set-up
- Connect the external signal to the TIM2_CH2 pin (PA.01) (pin 32 in CN7 connector)
- Connect the TIM2_CH1 pin(PA.00) (pin 34 in CN7 connector) to an oscilloscope to monitor the waveform.
@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
* <h3><center>© COPYRIGHT STMicroelectronics</center></h3>
*/
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