STM32CubeF1

/**
@page ADC_Regular_injected_groups ADC conversion example showing the usage of
the 2 ADC groups: regular group for ADC conversions on main stream and
injected group for ADC conversions limited on specific events (conversions
injected within main conversions stream),
using related peripherals (GPIO, DMA, Timer), voltage input from DAC, user
control by push button and LED

@verbatim
******************** (C) COPYRIGHT 2016 STMicroelectronics *******************
* @file ADC/ADC_Regular_injected_groups/readme.txt
* @author MCD Application Team
* @brief Description of the ADC conversion example
******************************************************************************
* @attention
*
* <h2><center>&copy; Copyright (c) 2016 STMicroelectronics.
* All rights reserved.</center></h2>
*
* This software component is licensed by ST under BSD 3-Clause license,
* the "License"; You may not use this file except in compliance with the
* License. You may obtain a copy of the License at:
* opensource.org/licenses/BSD-3-Clause
*
******************************************************************************
@endverbatim

@par Example Description

How to use the ADC peripheral to perform conversions using the two ADC groups:
regular group for ADC conversions on the main stream, and injected group for
ADC conversions limited to specific events (conversions injected into the
main conversion stream).

One compilation switch is available to select ADC configuration continuous mode
and external trigger (located in main.h):
- "ADC_TRIGGER_FROM_TIMER" defined: ADC is operating in not continuous mode
and conversions are trigger by external trigger: timer.
- "ADC_TRIGGER_FROM_TIMER" not defined: ADC is operating in continuous mode
and first conversion is trigger by software trigger.

One compilation switch is available to generate a waveform voltage
for test (located in main.h):
- "WAVEFORM_VOLTAGE_GENERATION_FOR_TEST" defined: For this example purpose, generates a
waveform voltage on a spare DAC channel (pin PA.04),
so user has just to connect a wire between DAC channel output and ADC input to run this example.
- "WAVEFORM_VOLTAGE_GENERATION_FOR_TEST" not defined: no voltage is generated, user has
to connect a voltage source to the selected ADC channel input to run this example.

Other peripherals related to ADC are used:
Mandatory:
- GPIO peripheral is used in analog mode to drive signal from device pin to
ADC input.
Optionally:
- Timer peripheral is used to trigger ADC conversions.
- DMA peripheral is used to transfer ADC converted data.

ADC settings:
- Regular group:
Conversion is triggered by external event (timer at 1kHz).
Number of conversions is set to 1 and continuous mode is disabled: there is
only 1 conversion at each trigger event.
- Injected group:
Conversion is software-triggered by a mere call to HAL_ADCEx_InjectedStart_IT()
to convert VREFINT channel at each press on user button.

ADC conversion results:
- ADC regular conversions results are transferred automatically by DMA, into variable
array "aADCxConvertedValues".
- When DMA transfer half-buffer and buffer lengths are reached, callbacks
HAL_ADC_ConvCpltCallback() and HAL_ADC_ConvCpltCallback() are called.
- ADC injected conversions results are retrieved upon JEOC interrupt by
HAL_ADCEx_InjectedConvCpltCallback() function.

Board settings:
- ADC is configured to convert ADC_CHANNEL_4 (pin PA.04).
- Channel configured on regular group:
The voltage input on ADC channel is provided from DAC channel.
ADC and DAC channel have been chosen to have the same pad shared at device level: pin PA.04.
==> Therefore, there is no external connection needed to run this example.
- Voltage is increasing at each click on push button, from 0 to maximum range in 4 steps.
Clicks on push button follow circular cycles: At clicks counter maximum value reached, counter is set back to 0.
- Channel configured on injected group:
The voltage input is provided from internal reference voltage VrefInt.

STM32VL-Discovery board's LEDs are be used to monitor the program execution status:
- Normal operation: LED3 is turned-on/off in function of ADC conversion
result.
- Turned-off if voltage measured by injected group is below voltage measured by regular group (average of results table)
- Turned-on if voltage measured by injected group is above voltage measured by regular group (average of results table)
- Error: In case of error, LED4 is toggling at a frequency of 1Hz.

@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 Directory contents

- ADC/ADC_Regular_injected_groups/Inc/stm32f1xx_hal_conf.h HAL configuration file
- ADC/ADC_Regular_injected_groups/Inc/stm32f1xx_it.h HAL interrupt handlers header file
- ADC/ADC_Regular_injected_groups/Inc/main.h Header for main.c module
- ADC/ADC_Regular_injected_groups/Src/stm32f1xx_it.c HAL interrupt handlers
- ADC/ADC_Regular_injected_groups/Src/main.c Main program
- ADC/ADC_Regular_injected_groups/Src/stm32f1xx_hal_msp.c HAL MSP file
- ADC/ADC_Regular_injected_groups/Src/system_stm32f1xx.c STM32F1xx system source file

@par Hardware and Software environment

- This example runs on STM32F1xx devices.

- This example has been tested with STM32VL-Discovery 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