Lee Kai Xuan / mbed-os

mbed-os

Fork of mbed-os by erkin yucel

targets/TARGET_STM/TARGET_STM32L4/analogin_api.c@0:f269e3021894, 2016-10-23 (annotated)

Committer:
elessair
Date:
Sun Oct 23 15:10:02 2016 +0000
Revision:
0:f269e3021894
Initial commit

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elessair 0:f269e3021894 1 /* mbed Microcontroller Library
elessair 0:f269e3021894 2 * Copyright (c) 2016, STMicroelectronics
elessair 0:f269e3021894 3 * All rights reserved.
elessair 0:f269e3021894 4 *
elessair 0:f269e3021894 5 * Redistribution and use in source and binary forms, with or without
elessair 0:f269e3021894 6 * modification, are permitted provided that the following conditions are met:
elessair 0:f269e3021894 7 *
elessair 0:f269e3021894 8 * 1. Redistributions of source code must retain the above copyright notice,
elessair 0:f269e3021894 9 * this list of conditions and the following disclaimer.
elessair 0:f269e3021894 10 * 2. Redistributions in binary form must reproduce the above copyright notice,
elessair 0:f269e3021894 11 * this list of conditions and the following disclaimer in the documentation
elessair 0:f269e3021894 12 * and/or other materials provided with the distribution.
elessair 0:f269e3021894 13 * 3. Neither the name of STMicroelectronics nor the names of its contributors
elessair 0:f269e3021894 14 * may be used to endorse or promote products derived from this software
elessair 0:f269e3021894 15 * without specific prior written permission.
elessair 0:f269e3021894 16 *
elessair 0:f269e3021894 17 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
elessair 0:f269e3021894 18 * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
elessair 0:f269e3021894 19 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
elessair 0:f269e3021894 20 * DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE LIABLE
elessair 0:f269e3021894 21 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
elessair 0:f269e3021894 22 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
elessair 0:f269e3021894 23 * SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER
elessair 0:f269e3021894 24 * CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
elessair 0:f269e3021894 25 * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
elessair 0:f269e3021894 26 * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
elessair 0:f269e3021894 27 */
elessair 0:f269e3021894 28 #include "mbed_assert.h"
elessair 0:f269e3021894 29 #include "analogin_api.h"
elessair 0:f269e3021894 30
elessair 0:f269e3021894 31 #if DEVICE_ANALOGIN
elessair 0:f269e3021894 32
elessair 0:f269e3021894 33 #include "wait_api.h"
elessair 0:f269e3021894 34 #include "cmsis.h"
elessair 0:f269e3021894 35 #include "pinmap.h"
elessair 0:f269e3021894 36 #include "mbed_error.h"
elessair 0:f269e3021894 37 #include "PeripheralPins.h"
elessair 0:f269e3021894 38
elessair 0:f269e3021894 39 ADC_HandleTypeDef AdcHandle;
elessair 0:f269e3021894 40
elessair 0:f269e3021894 41 int adc_inited = 0;
elessair 0:f269e3021894 42
elessair 0:f269e3021894 43 void analogin_init(analogin_t *obj, PinName pin)
elessair 0:f269e3021894 44 {
elessair 0:f269e3021894 45 // Get the peripheral name from the pin and assign it to the object
elessair 0:f269e3021894 46 obj->adc = (ADCName)pinmap_peripheral(pin, PinMap_ADC);
elessair 0:f269e3021894 47 MBED_ASSERT(obj->adc != (ADCName)NC);
elessair 0:f269e3021894 48
elessair 0:f269e3021894 49 // Get the pin function and assign the used channel to the object
elessair 0:f269e3021894 50 uint32_t function = pinmap_function(pin, PinMap_ADC);
elessair 0:f269e3021894 51 MBED_ASSERT(function != (uint32_t)NC);
elessair 0:f269e3021894 52 obj->channel = STM_PIN_CHANNEL(function);
elessair 0:f269e3021894 53
elessair 0:f269e3021894 54 // Configure GPIO excepted for internal channels (Temperature, Vref, Vbat, ...)
elessair 0:f269e3021894 55 // ADC Internal Channels "pins" are described in PinNames.h and must have a value >= 0xF0
elessair 0:f269e3021894 56 if (pin < 0xF0) {
elessair 0:f269e3021894 57 pinmap_pinout(pin, PinMap_ADC);
elessair 0:f269e3021894 58 }
elessair 0:f269e3021894 59
elessair 0:f269e3021894 60 // Save pin number for the read function
elessair 0:f269e3021894 61 obj->pin = pin;
elessair 0:f269e3021894 62
elessair 0:f269e3021894 63 // The ADC initialization is done once
elessair 0:f269e3021894 64 if (adc_inited == 0) {
elessair 0:f269e3021894 65 adc_inited = 1;
elessair 0:f269e3021894 66
elessair 0:f269e3021894 67 // Enable ADC clock
elessair 0:f269e3021894 68 __HAL_RCC_ADC_CLK_ENABLE();
elessair 0:f269e3021894 69 __HAL_RCC_ADC_CONFIG(RCC_ADCCLKSOURCE_SYSCLK);
elessair 0:f269e3021894 70
elessair 0:f269e3021894 71 AdcHandle.Instance = (ADC_TypeDef *)(obj->adc);
elessair 0:f269e3021894 72
elessair 0:f269e3021894 73 // Configure ADC
elessair 0:f269e3021894 74 AdcHandle.Init.ClockPrescaler = ADC_CLOCK_ASYNC_DIV2; // Asynchronous clock mode, input ADC clock
elessair 0:f269e3021894 75 AdcHandle.Init.Resolution = ADC_RESOLUTION_12B;
elessair 0:f269e3021894 76 AdcHandle.Init.DataAlign = ADC_DATAALIGN_RIGHT;
elessair 0:f269e3021894 77 AdcHandle.Init.ScanConvMode = DISABLE; // Sequencer disabled (ADC conversion on only 1 channel: channel set on rank 1)
elessair 0:f269e3021894 78 AdcHandle.Init.EOCSelection = ADC_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).
elessair 0:f269e3021894 79 AdcHandle.Init.LowPowerAutoWait = DISABLE;
elessair 0:f269e3021894 80 AdcHandle.Init.ContinuousConvMode = DISABLE; // Continuous mode disabled to have only 1 conversion at each conversion trig
elessair 0:f269e3021894 81 AdcHandle.Init.NbrOfConversion = 1; // Parameter discarded because sequencer is disabled
elessair 0:f269e3021894 82 AdcHandle.Init.DiscontinuousConvMode = DISABLE; // Parameter discarded because sequencer is disabled
elessair 0:f269e3021894 83 AdcHandle.Init.NbrOfDiscConversion = 1; // Parameter discarded because sequencer is disabled
elessair 0:f269e3021894 84 AdcHandle.Init.ExternalTrigConv = ADC_SOFTWARE_START; // Software start to trig the 1st conversion manually, without external event
elessair 0:f269e3021894 85 AdcHandle.Init.ExternalTrigConvEdge = ADC_EXTERNALTRIGCONVEDGE_NONE;
elessair 0:f269e3021894 86 AdcHandle.Init.DMAContinuousRequests = DISABLE;
elessair 0:f269e3021894 87 AdcHandle.Init.Overrun = ADC_OVR_DATA_OVERWRITTEN; // DR register is overwritten with the last conversion result in case of overrun
elessair 0:f269e3021894 88 AdcHandle.Init.OversamplingMode = DISABLE; // No oversampling
elessair 0:f269e3021894 89
elessair 0:f269e3021894 90 if (HAL_ADC_Init(&AdcHandle) != HAL_OK) {
elessair 0:f269e3021894 91 error("Cannot initialize ADC\n");
elessair 0:f269e3021894 92 }
elessair 0:f269e3021894 93 }
elessair 0:f269e3021894 94 }
elessair 0:f269e3021894 95
elessair 0:f269e3021894 96 static inline uint16_t adc_read(analogin_t *obj)
elessair 0:f269e3021894 97 {
elessair 0:f269e3021894 98 ADC_ChannelConfTypeDef sConfig = {0};
elessair 0:f269e3021894 99
elessair 0:f269e3021894 100 AdcHandle.Instance = (ADC_TypeDef *)(obj->adc);
elessair 0:f269e3021894 101
elessair 0:f269e3021894 102 // Configure ADC channel
elessair 0:f269e3021894 103 switch (obj->channel) {
elessair 0:f269e3021894 104 case 0:
elessair 0:f269e3021894 105 sConfig.Channel = ADC_CHANNEL_VREFINT;
elessair 0:f269e3021894 106 break;
elessair 0:f269e3021894 107 case 1:
elessair 0:f269e3021894 108 sConfig.Channel = ADC_CHANNEL_1;
elessair 0:f269e3021894 109 break;
elessair 0:f269e3021894 110 case 2:
elessair 0:f269e3021894 111 sConfig.Channel = ADC_CHANNEL_2;
elessair 0:f269e3021894 112 break;
elessair 0:f269e3021894 113 case 3:
elessair 0:f269e3021894 114 sConfig.Channel = ADC_CHANNEL_3;
elessair 0:f269e3021894 115 break;
elessair 0:f269e3021894 116 case 4:
elessair 0:f269e3021894 117 sConfig.Channel = ADC_CHANNEL_4;
elessair 0:f269e3021894 118 break;
elessair 0:f269e3021894 119 case 5:
elessair 0:f269e3021894 120 sConfig.Channel = ADC_CHANNEL_5;
elessair 0:f269e3021894 121 break;
elessair 0:f269e3021894 122 case 6:
elessair 0:f269e3021894 123 sConfig.Channel = ADC_CHANNEL_6;
elessair 0:f269e3021894 124 break;
elessair 0:f269e3021894 125 case 7:
elessair 0:f269e3021894 126 sConfig.Channel = ADC_CHANNEL_7;
elessair 0:f269e3021894 127 break;
elessair 0:f269e3021894 128 case 8:
elessair 0:f269e3021894 129 sConfig.Channel = ADC_CHANNEL_8;
elessair 0:f269e3021894 130 break;
elessair 0:f269e3021894 131 case 9:
elessair 0:f269e3021894 132 sConfig.Channel = ADC_CHANNEL_9;
elessair 0:f269e3021894 133 break;
elessair 0:f269e3021894 134 case 10:
elessair 0:f269e3021894 135 sConfig.Channel = ADC_CHANNEL_10;
elessair 0:f269e3021894 136 break;
elessair 0:f269e3021894 137 case 11:
elessair 0:f269e3021894 138 sConfig.Channel = ADC_CHANNEL_11;
elessair 0:f269e3021894 139 break;
elessair 0:f269e3021894 140 case 12:
elessair 0:f269e3021894 141 sConfig.Channel = ADC_CHANNEL_12;
elessair 0:f269e3021894 142 break;
elessair 0:f269e3021894 143 case 13:
elessair 0:f269e3021894 144 sConfig.Channel = ADC_CHANNEL_13;
elessair 0:f269e3021894 145 break;
elessair 0:f269e3021894 146 case 14:
elessair 0:f269e3021894 147 sConfig.Channel = ADC_CHANNEL_14;
elessair 0:f269e3021894 148 break;
elessair 0:f269e3021894 149 case 15:
elessair 0:f269e3021894 150 sConfig.Channel = ADC_CHANNEL_15;
elessair 0:f269e3021894 151 break;
elessair 0:f269e3021894 152 case 16:
elessair 0:f269e3021894 153 sConfig.Channel = ADC_CHANNEL_16;
elessair 0:f269e3021894 154 break;
elessair 0:f269e3021894 155 case 17:
elessair 0:f269e3021894 156 sConfig.Channel = ADC_CHANNEL_TEMPSENSOR;
elessair 0:f269e3021894 157 break;
elessair 0:f269e3021894 158 case 18:
elessair 0:f269e3021894 159 sConfig.Channel = ADC_CHANNEL_VBAT;
elessair 0:f269e3021894 160 break;
elessair 0:f269e3021894 161 default:
elessair 0:f269e3021894 162 return 0;
elessair 0:f269e3021894 163 }
elessair 0:f269e3021894 164
elessair 0:f269e3021894 165 sConfig.Rank = ADC_REGULAR_RANK_1;
elessair 0:f269e3021894 166 sConfig.SamplingTime = ADC_SAMPLETIME_47CYCLES_5;
elessair 0:f269e3021894 167 sConfig.SingleDiff = ADC_SINGLE_ENDED;
elessair 0:f269e3021894 168 sConfig.OffsetNumber = ADC_OFFSET_NONE;
elessair 0:f269e3021894 169 sConfig.Offset = 0;
elessair 0:f269e3021894 170
elessair 0:f269e3021894 171 HAL_ADC_ConfigChannel(&AdcHandle, &sConfig);
elessair 0:f269e3021894 172
elessair 0:f269e3021894 173 HAL_ADC_Start(&AdcHandle); // Start conversion
elessair 0:f269e3021894 174
elessair 0:f269e3021894 175 // Wait end of conversion and get value
elessair 0:f269e3021894 176 if (HAL_ADC_PollForConversion(&AdcHandle, 10) == HAL_OK) {
elessair 0:f269e3021894 177 return (HAL_ADC_GetValue(&AdcHandle));
elessair 0:f269e3021894 178 } else {
elessair 0:f269e3021894 179 return 0;
elessair 0:f269e3021894 180 }
elessair 0:f269e3021894 181 }
elessair 0:f269e3021894 182
elessair 0:f269e3021894 183 uint16_t analogin_read_u16(analogin_t *obj)
elessair 0:f269e3021894 184 {
elessair 0:f269e3021894 185 uint16_t value = adc_read(obj);
elessair 0:f269e3021894 186 // 12-bit to 16-bit conversion
elessair 0:f269e3021894 187 value = ((value << 4) & (uint16_t)0xFFF0) | ((value >> 8) & (uint16_t)0x000F);
elessair 0:f269e3021894 188 return value;
elessair 0:f269e3021894 189 }
elessair 0:f269e3021894 190
elessair 0:f269e3021894 191 float analogin_read(analogin_t *obj)
elessair 0:f269e3021894 192 {
elessair 0:f269e3021894 193 uint16_t value = adc_read(obj);
elessair 0:f269e3021894 194 return (float)value * (1.0f / (float)0xFFF); // 12 bits range
elessair 0:f269e3021894 195 }
elessair 0:f269e3021894 196
elessair 0:f269e3021894 197 #endif