83 lines
3.5 KiB
Plaintext
83 lines
3.5 KiB
Plaintext
/**
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@page ADC_RegularConversion_DMA ADC3 conversion using DMA for Data transfer
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@verbatim
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******************** (C) COPYRIGHT 2017 STMicroelectronics *******************
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* @file ADC/ADC_RegularConversion_DMA/readme.txt
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* @author MCD Application Team
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* @brief Description of the ADC RegularConversion DMA example.
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******************************************************************************
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* @attention
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*
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* Copyright (c) 2017 STMicroelectronics.
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* All rights reserved.
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*
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* This software is licensed under terms that can be found in the LICENSE file
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* in the root directory of this software component.
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* If no LICENSE file comes with this software, it is provided AS-IS.
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*
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******************************************************************************
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@endverbatim
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@par Example Description
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How to use the ADC1 and DMA to transfer continuously converted data from
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ADC1 to memory.
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The ADC1 is configured to convert continuously channel8 (ADC1_IN8, pin PB.00 on STM32F407xx Device).
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Each time an end of conversion occurs the DMA transfers(DMA2 Stream0, Channel 0), in circular mode,
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the converted data from ADC1 DR register to the uhADCxConvertedValue variable.
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In this example, the system clock is 84MHz, APB2 = 42MHz and ADC clock = APB2/2.
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Since ADC1 clock is 21 MHz and sampling time is set to 3 cycles, the conversion
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time to 12bit data is 12 cycles so the total conversion time is (12+3)/21= 0.71us(7.14Msps).
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User can vary the ADC1 channel8(for STM32F401C-Discovery voltage probing external
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power supply on PB.00 Gpio pin.
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STM32 DISCO boards LEDs can be used to monitor the transfer status:
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- LED4 is ON when the conversion is complete.
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- LED5 is ON when there are an error in initialization.
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@note Care must be taken when using HAL_Delay(), this function provides accurate delay (in milliseconds)
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based on variable incremented in SysTick ISR. This implies that if HAL_Delay() is called from
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a peripheral ISR process, then the SysTick interrupt must have higher priority (numerically lower)
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than the peripheral interrupt. Otherwise the caller ISR process will be blocked.
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To change the SysTick interrupt priority you have to use HAL_NVIC_SetPriority() function.
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@note The application needs to ensure that the SysTick time base is always set to 1 millisecond
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to have correct HAL operation.
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@par Keywords
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Analog, ADC, Analog to Digital Converter, Regular Conversion, DMA, Continuous Conversion
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@par Directory contents
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- ADC/ADC_RegularConversion_DMA/Inc/stm32f4xx_hal_conf.h HAL configuration file
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- ADC/ADC_RegularConversion_DMA/Inc/stm32f4xx_it.h Interrupt handlers header file
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- ADC/ADC_RegularConversion_DMA/Inc/main.h Main program header file
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- ADC/ADC_RegularConversion_DMA/Src/stm32f4xx_it.c Interrupt handlers
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- ADC/ADC_RegularConversion_DMA/Src/main.c Main program
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- ADC/ADC_RegularConversion_DMA/Src/stm32f4xx_hal_msp.c HAL MSP module
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- ADC/ADC_RegularConversion_DMA/Src/system_stm32f4xx.c STM32F4xx system clock configuration file
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@par Hardware and Software environment
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- This example runs on STM32F401xCx device.
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- This example has been tested with STMicroelectronics STM32F401-Discovery RevB
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boards and can be easily tailored to any other supported device
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and development board.
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@par How to use it ?
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In order to make the program work, you must do the following :
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- Open your preferred toolchain
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- Rebuild all files and load your image into target memory
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- Run the example
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*/
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