tool/mbed/mbed-sdk/libraries/mbed/targets/hal/TARGET_STM/TARGET_STM32L1/analogin_api.c

   1 /* mbed Microcontroller Library
   2  * Copyright (c) 2014, STMicroelectronics
   3  * All rights reserved.
   4  *
   5  * Redistribution and use in source and binary forms, with or without
   6  * modification, are permitted provided that the following conditions are met:
   7  *
   8  * 1. Redistributions of source code must retain the above copyright notice,
   9  *    this list of conditions and the following disclaimer.
  10  * 2. Redistributions in binary form must reproduce the above copyright notice,
  11  *    this list of conditions and the following disclaimer in the documentation
  12  *    and/or other materials provided with the distribution.
  13  * 3. Neither the name of STMicroelectronics nor the names of its contributors
  14  *    may be used to endorse or promote products derived from this software
  15  *    without specific prior written permission.
  16  *
  17  * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
  18  * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
  19  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
  20  * DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE LIABLE
  21  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
  22  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
  23  * SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER
  24  * CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
  25  * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
  26  * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
  27  */
  28 #include "mbed_assert.h"
  29 #include "analogin_api.h"
  30
  31 #if DEVICE_ANALOGIN
  32
  33 #include "wait_api.h"
  34 #include "cmsis.h"
  35 #include "pinmap.h"
  36 #include "PeripheralPins.h"
  37
  38 ADC_HandleTypeDef AdcHandle;
  39
  40 int adc_inited = 0;
  41
  42 void analogin_init(analogin_t *obj, PinName pin)
  43 {
  44     RCC_OscInitTypeDef RCC_OscInitStruct;
  45
  46     // Get the peripheral name from the pin and assign it to the object
  47     obj->adc = (ADCName)pinmap_peripheral(pin, PinMap_ADC);
  48
  49     MBED_ASSERT(obj->adc != (ADCName)NC);
  50
  51     // Configure GPIO
  52     pinmap_pinout(pin, PinMap_ADC);
  53
  54     // Save pin number for the read function
  55     obj->pin = pin;
  56
  57     // The ADC initialization is done once
  58     if (adc_inited == 0) {
  59         adc_inited = 1;
  60
  61         // Enable the HSI (to clock the ADC)
  62         RCC_OscInitStruct.OscillatorType = RCC_OSCILLATORTYPE_HSI;
  63         RCC_OscInitStruct.HSIState       = RCC_HSI_ON;
  64         RCC_OscInitStruct.PLL.PLLState   = RCC_PLL_NONE;
  65         HAL_RCC_OscConfig(&RCC_OscInitStruct);
  66
  67         AdcHandle.Instance = (ADC_TypeDef *)(obj->adc);
  68
  69         // Enable ADC clock
  70         __ADC1_CLK_ENABLE();
  71
  72         // Configure ADC
  73         AdcHandle.Init.ClockPrescaler        = ADC_CLOCK_ASYNC_DIV4;
  74         AdcHandle.Init.Resolution            = ADC_RESOLUTION12b;
  75         AdcHandle.Init.DataAlign             = ADC_DATAALIGN_RIGHT;
  76         AdcHandle.Init.ScanConvMode          = DISABLE;                       // Sequencer disabled (ADC conversion on only 1 channel: channel set on rank 1)
  77         AdcHandle.Init.EOCSelection          = EOC_SINGLE_CONV;               // On STM32L1xx ADC, overrun detection is enabled only if EOC selection is set to each conversion (or transfer by DMA enabled, this is not the case in this example).
  78         AdcHandle.Init.LowPowerAutoWait      = ADC_AUTOWAIT_UNTIL_DATA_READ;  // Enable the dynamic low power Auto Delay: new conversion start only when the previous conversion (for regular group) or previous sequence (for injected group) has been treated by user software.
  79         AdcHandle.Init.LowPowerAutoPowerOff  = ADC_AUTOPOWEROFF_IDLE_PHASE;   // Enable the auto-off mode: the ADC automatically powers-off after a conversion and automatically wakes-up when a new conversion is triggered (with startup time between trigger and start of sampling).
  80         AdcHandle.Init.ChannelsBank          = ADC_CHANNELS_BANK_A;
  81         AdcHandle.Init.ContinuousConvMode    = DISABLE;                       // Continuous mode disabled to have only 1 conversion at each conversion trig
  82         AdcHandle.Init.NbrOfConversion       = 1;                             // Parameter discarded because sequencer is disabled
  83         AdcHandle.Init.DiscontinuousConvMode = DISABLE;                       // Parameter discarded because sequencer is disabled
  84         AdcHandle.Init.NbrOfDiscConversion   = 1;                             // Parameter discarded because sequencer is disabled
  85         AdcHandle.Init.ExternalTrigConv      = 0;                             // Not used
  86         AdcHandle.Init.ExternalTrigConvEdge  = ADC_EXTERNALTRIGCONVEDGE_NONE;
  87         AdcHandle.Init.DMAContinuousRequests = DISABLE;
  88         HAL_ADC_Init(&AdcHandle);
  89     }
  90 }
  91
  92 static inline uint16_t adc_read(analogin_t *obj)
  93 {
  94     ADC_ChannelConfTypeDef sConfig;
  95
  96     AdcHandle.Instance = (ADC_TypeDef *)(obj->adc);
  97
  98     // Configure ADC channel
  99     switch (obj->pin) {
 100         case PA_0:
 101             sConfig.Channel = ADC_CHANNEL_0;
 102             break;
 103         case PA_1:
 104             sConfig.Channel = ADC_CHANNEL_1;
 105             break;
 106         case PA_2:
 107             sConfig.Channel = ADC_CHANNEL_2;
 108             break;
 109         case PA_3:
 110             sConfig.Channel = ADC_CHANNEL_3;
 111             break;
 112         case PA_4:
 113             sConfig.Channel = ADC_CHANNEL_4;
 114             break;
 115         case PA_5:
 116             sConfig.Channel = ADC_CHANNEL_5;
 117             break;
 118         case PA_6:
 119             sConfig.Channel = ADC_CHANNEL_6;
 120             break;
 121         case PA_7:
 122             sConfig.Channel = ADC_CHANNEL_7;
 123             break;
 124         case PB_0:
 125             sConfig.Channel = ADC_CHANNEL_8;
 126             break;
 127         case PB_1:
 128             sConfig.Channel = ADC_CHANNEL_9;
 129             break;
 130         case PC_0:
 131             sConfig.Channel = ADC_CHANNEL_10;
 132             break;
 133         case PC_1:
 134             sConfig.Channel = ADC_CHANNEL_11;
 135             break;
 136         case PC_2:
 137             sConfig.Channel = ADC_CHANNEL_12;
 138             break;
 139         case PC_3:
 140             sConfig.Channel = ADC_CHANNEL_13;
 141             break;
 142         case PC_4:
 143             sConfig.Channel = ADC_CHANNEL_14;
 144             break;
 145         case PC_5:
 146             sConfig.Channel = ADC_CHANNEL_15;
 147             break;
 148         case PB_12:
 149             sConfig.Channel = ADC_CHANNEL_18;
 150             break;
 151         case PB_13:
 152             sConfig.Channel = ADC_CHANNEL_19;
 153             break;
 154         case PB_14:
 155             sConfig.Channel = ADC_CHANNEL_20;
 156             break;
 157         case PB_15:
 158             sConfig.Channel = ADC_CHANNEL_21;
 159             break;
 160         default:
 161             return 0;
 162     }
 163
 164     sConfig.Rank         = ADC_REGULAR_RANK_1;
 165     sConfig.SamplingTime = ADC_SAMPLETIME_16CYCLES;
 166
 167     HAL_ADC_ConfigChannel(&AdcHandle, &sConfig);
 168
 169     HAL_ADC_Start(&AdcHandle); // Start conversion
 170
 171     // Wait end of conversion and get value
 172     if (HAL_ADC_PollForConversion(&AdcHandle, 10) == HAL_OK) {
 173         return (HAL_ADC_GetValue(&AdcHandle));
 174     } else {
 175         return 0;
 176     }
 177 }
 178
 179 uint16_t analogin_read_u16(analogin_t *obj)
 180 {
 181     uint16_t value = adc_read(obj);
 182     // 12-bit to 16-bit conversion
 183     value = ((value << 4) & (uint16_t)0xFFF0) | ((value >> 8) & (uint16_t)0x000F);
 184     return value;
 185 }
 186
 187 float analogin_read(analogin_t *obj)
 188 {
 189     uint16_t value = adc_read(obj);
 190     return (float)value * (1.0f / (float)0xFFF); // 12 bits range
 191 }
 192
 193 #endif