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/**
@page ADC_SingleConversion_TriggerSW_DMA_Init ADC example
@verbatim
******************************************************************************
* @file Examples_LL/ADC/ADC_SingleConversion_TriggerSW_DMA_Init/readme.txt
* @author MCD Application Team
* @brief Description of the ADC_SingleConversion_TriggerSW_DMA_Init 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
How to use an ADC peripheral to perform a single ADC conversion on a channel,
at each software start. This example uses the DMA programming model
(for polling or interrupt programming models, refer to other examples).
This example is based on the STM32WBxx ADC LL API. The
peripheral initialization is done using LL unitary service functions
for optimization purposes (performance and size).
Example configuration:
ADC is configured to convert a single channel, in single conversion mode,
from SW trigger.
DMA is configured to transfer conversion data in an array, in circular mode.
Note: In this example, array size can be set to 1 (equivalent to a single variable)
to have a scenario comparable to other ADC examples using programming model
polling or interruption.
Size of array can be modified with literal ADC_CONVERTED_DATA_BUFFER_SIZE).
Example execution:
At each press on User push-button (SW1), the ADC performs 1 conversion of the selected
channel.
DMA transfers conversion data to the array.
When DMA reaches the selected number of transfers,
DMA half transfer and transfer complete interruptions occurs.
Data array is updated indefinitely (DMA in circular mode).
LED2 is turned off at DMA half transfer and turned on at DMA transfer complete.
For debug: variables to monitor with debugger watch window:
- "aADCxConvertedData": ADC group regular conversion data
- "aADCxConvertedData_Voltage_mVolt": ADC conversion data computation to physical values (array of data)
After 4 steps the DMA complete the transfer and the following scenario must be displayed:
-First press: aADCxConvertedData [0] displayed.
-Second press: aADCxConvertedData [1], aADCxConvertedData_Voltage_mVolt [0] and aADCxConvertedData_Voltage_mVolt [1] displayed.
-Third press: aADCxConvertedData [2] displayed.
-Fourth press: aADCxConvertedData [3], aADCxConvertedData_Voltage_mVolt [2] and aADCxConvertedData_Voltage_mVolt [3] displayed.
LED2 is blinking every 1 sec in case of error.
Connection needed:
None.
Note: Optionally, a voltage can be supplied to the analog input pin (cf pin below),
between 0V and Vdda=3.3V, to perform a ADC conversion on a determined
voltage level.
Otherwise, this pin can be let floating (in this case ADC conversion data
will be undetermined).
Other peripherals used:
1 GPIO for User push-button (SW1)
1 GPIO for LED2
1 GPIO for analog input: PA.01 (Arduino connector CN8 pin A2, Morpho connector CN7 pin 32)
DMA
@par Keywords
ADC, analog digital converter, analog, conversion, voltage, channel, analog input, DMA transfer
@par Directory contents
- ADC/ADC_SingleConversion_TriggerSW_DMA_Init/Inc/stm32wbxx_it.h Interrupt handlers header file
- ADC/ADC_SingleConversion_TriggerSW_DMA_Init/Inc/main.h Header for main.c module
- ADC/ADC_SingleConversion_TriggerSW_DMA_Init/Inc/stm32_assert.h Template file to include assert_failed function
- ADC/ADC_SingleConversion_TriggerSW_DMA_Init/Src/stm32wbxx_it.c Interrupt handlers
- ADC/ADC_SingleConversion_TriggerSW_DMA_Init/Src/main.c Main program
- ADC/ADC_SingleConversion_TriggerSW_DMA_Init/Src/system_stm32wbxx.c STM32WBxx system source file
@par Hardware and Software environment
- This example runs on STM32WB55RGVx devices.
- This example has been tested with P-NUCLEO-WB55 board and can be
easily tailored to any other supported device and development board.
@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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