/**
@page TIM_OCInactive TIM Output Compare Active example
@verbatim
******************** (C) COPYRIGHT 2017 STMicroelectronics *******************
* @file TIM/TIM_OCActive/readme.txt
* @author MCD Application Team
* @brief This example shows how to configure the Timer to generate four
* delayed signals.
******************************************************************************
* @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 configure the TIM peripheral in Output Compare Inactive
mode with the corresponding Interrupt requests for each channel.
The TIM2CLK frequency is set to SystemCoreClock / 2 (Hz), and the objective is
to get TIM2 counter clock at 2 KHz so the Prescaler is computed as following:
- Prescaler = (TIM2CLK / TIM2 counter clock) - 1
SystemCoreClock is set to 180 MHz for STM32F4xx devices
The TIM2 CCR1 register value is equal to 1000:
TIM2_CC1 delay = CCR1_Val/TIM2 counter clock = 500 ms
so the PA.00 is reset after a delay equal to 500 ms.
The TIM2 CCR2 register value is equal to 500:
TIM2_CC2 delay = CCR2_Val/TIM2 counter clock = 250 ms
so the PA.01 is reset after a delay equal to 250 ms.
The TIM2 CCR3 register value is equal to 250:
TIM2_CC3 delay = CCR3_Val/TIM2 counter clock = 125 ms
so the PA.02 is reset after a delay equal to 125 ms.
The TIM2 CCR4 register value is equal to 125:
TIM2_CC4 delay = CCR4_Val/TIM2 counter clock = 62.5 ms
so the PA.03 is reset after a delay equal to 62.5 ms.
While the counter is lower than the Output compare registers values, which
determines the Output delay, the PG.06, PG.07, PG.10 and PG.12 pin are turned ON.
When the counter value reaches the Output compare registers values, the Output
Compare interrupts are generated and, in the handler routine, these pins are turned OFF.
@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, Output, Compare, InActive, Signals, Delay, Frequency
@par Directory contents
- TIM/TIM_OCInactive/Inc/stm32f4xx_hal_conf.h HAL configuration file
- TIM/TIM_OCInactive/Inc/stm32f4xx_it.h Interrupt handlers header file
- TIM/TIM_OCInactive/Inc/main.h Main program header file
- TIM/TIM_OCInactive/Src/stm32f4xx_it.c Interrupt handlers
- TIM/TIM_OCInactive/Src/main.c Main program
- TIM/TIM_OCInactive/Src/stm32f4xx_hal_msp.c HAL MSP module
- TIM/TIM_OCInactive/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 the following pins to an oscilloscope to monitor the different
waveforms:
- Use LED1 connected to PG.06
- Use LED2 connected to PG.07
- Use LED3 connected to PG.10
- Use LED4 connected to PG.12
@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
*/
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