mbed os with nrf51 internal bandgap enabled to read battery level

Dependents:   BLE_file_test BLE_Blink ExternalEncoder

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

Who changed what in which revision?

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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 "PeripheralPins.h"
elessair 0:f269e3021894 37 #include "mbed_error.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 // Get the peripheral name from the pin and assign it to the object
elessair 0:f269e3021894 45 obj->adc = (ADCName)pinmap_peripheral(pin, PinMap_ADC);
elessair 0:f269e3021894 46 MBED_ASSERT(obj->adc != (ADCName)NC);
elessair 0:f269e3021894 47
elessair 0:f269e3021894 48 // Get the functions (adc channel) from the pin and assign it to the object
elessair 0:f269e3021894 49 uint32_t function = pinmap_function(pin, PinMap_ADC);
elessair 0:f269e3021894 50 MBED_ASSERT(function != (uint32_t)NC);
elessair 0:f269e3021894 51 obj->channel = STM_PIN_CHANNEL(function);
elessair 0:f269e3021894 52
elessair 0:f269e3021894 53 // Configure GPIO excepted for internal channels (Temperature, Vref, Vbat, ...)
elessair 0:f269e3021894 54 // ADC Internal Channels "pins" are described in PinNames.h and must have a value >= 0xF0
elessair 0:f269e3021894 55 if (pin < 0xF0) {
elessair 0:f269e3021894 56 pinmap_pinout(pin, PinMap_ADC);
elessair 0:f269e3021894 57 }
elessair 0:f269e3021894 58
elessair 0:f269e3021894 59 // Save pin number for the read function
elessair 0:f269e3021894 60 obj->pin = pin;
elessair 0:f269e3021894 61
elessair 0:f269e3021894 62 // The ADC initialization is done once
elessair 0:f269e3021894 63 if (adc_inited == 0) {
elessair 0:f269e3021894 64 adc_inited = 1;
elessair 0:f269e3021894 65
elessair 0:f269e3021894 66 // Enable ADC clock
elessair 0:f269e3021894 67 __ADC1_CLK_ENABLE();
elessair 0:f269e3021894 68
elessair 0:f269e3021894 69 // Configure ADC
elessair 0:f269e3021894 70 AdcHandle.Instance = (ADC_TypeDef *)(obj->adc);
elessair 0:f269e3021894 71 AdcHandle.Init.ClockPrescaler = ADC_CLOCK_SYNC_PCLK_DIV4;
elessair 0:f269e3021894 72 AdcHandle.Init.Resolution = ADC_RESOLUTION12b;
elessair 0:f269e3021894 73 AdcHandle.Init.DataAlign = ADC_DATAALIGN_RIGHT;
elessair 0:f269e3021894 74 AdcHandle.Init.ScanConvMode = DISABLE;
elessair 0:f269e3021894 75 AdcHandle.Init.EOCSelection = EOC_SINGLE_CONV;
elessair 0:f269e3021894 76 AdcHandle.Init.LowPowerAutoWait = DISABLE;
elessair 0:f269e3021894 77 AdcHandle.Init.LowPowerAutoPowerOff = DISABLE;
elessair 0:f269e3021894 78 AdcHandle.Init.ContinuousConvMode = DISABLE;
elessair 0:f269e3021894 79 AdcHandle.Init.DiscontinuousConvMode = DISABLE;
elessair 0:f269e3021894 80 AdcHandle.Init.ExternalTrigConv = ADC_SOFTWARE_START;
elessair 0:f269e3021894 81 AdcHandle.Init.ExternalTrigConvEdge = ADC_EXTERNALTRIGCONVEDGE_NONE;
elessair 0:f269e3021894 82 AdcHandle.Init.DMAContinuousRequests = DISABLE;
elessair 0:f269e3021894 83 AdcHandle.Init.Overrun = OVR_DATA_OVERWRITTEN;
elessair 0:f269e3021894 84 if (HAL_ADC_Init(&AdcHandle) != HAL_OK) {
elessair 0:f269e3021894 85 error("Cannot initialize ADC");
elessair 0:f269e3021894 86 }
elessair 0:f269e3021894 87 // Run the ADC calibration
elessair 0:f269e3021894 88 if (HAL_ADCEx_Calibration_Start(&AdcHandle) != HAL_OK) {
elessair 0:f269e3021894 89 error("Cannot Start ADC_Calibration");
elessair 0:f269e3021894 90 }
elessair 0:f269e3021894 91 }
elessair 0:f269e3021894 92 }
elessair 0:f269e3021894 93
elessair 0:f269e3021894 94 static inline uint16_t adc_read(analogin_t *obj) {
elessair 0:f269e3021894 95 ADC_ChannelConfTypeDef sConfig;
elessair 0:f269e3021894 96
elessair 0:f269e3021894 97 AdcHandle.Instance = (ADC_TypeDef *)(obj->adc);
elessair 0:f269e3021894 98
elessair 0:f269e3021894 99 // Configure ADC channel
elessair 0:f269e3021894 100 sConfig.Rank = ADC_RANK_CHANNEL_NUMBER;
elessair 0:f269e3021894 101 #if defined (TARGET_STM32F091RC)
elessair 0:f269e3021894 102 sConfig.SamplingTime = ADC_SAMPLETIME_13CYCLES_5;
elessair 0:f269e3021894 103 #else
elessair 0:f269e3021894 104 sConfig.SamplingTime = ADC_SAMPLETIME_7CYCLES_5;
elessair 0:f269e3021894 105 #endif
elessair 0:f269e3021894 106
elessair 0:f269e3021894 107 switch (obj->channel) {
elessair 0:f269e3021894 108 case 0:
elessair 0:f269e3021894 109 sConfig.Channel = ADC_CHANNEL_0;
elessair 0:f269e3021894 110 break;
elessair 0:f269e3021894 111 case 1:
elessair 0:f269e3021894 112 sConfig.Channel = ADC_CHANNEL_1;
elessair 0:f269e3021894 113 break;
elessair 0:f269e3021894 114 case 2:
elessair 0:f269e3021894 115 sConfig.Channel = ADC_CHANNEL_2;
elessair 0:f269e3021894 116 break;
elessair 0:f269e3021894 117 case 3:
elessair 0:f269e3021894 118 sConfig.Channel = ADC_CHANNEL_3;
elessair 0:f269e3021894 119 break;
elessair 0:f269e3021894 120 case 4:
elessair 0:f269e3021894 121 sConfig.Channel = ADC_CHANNEL_4;
elessair 0:f269e3021894 122 break;
elessair 0:f269e3021894 123 case 5:
elessair 0:f269e3021894 124 sConfig.Channel = ADC_CHANNEL_5;
elessair 0:f269e3021894 125 break;
elessair 0:f269e3021894 126 case 6:
elessair 0:f269e3021894 127 sConfig.Channel = ADC_CHANNEL_6;
elessair 0:f269e3021894 128 break;
elessair 0:f269e3021894 129 case 7:
elessair 0:f269e3021894 130 sConfig.Channel = ADC_CHANNEL_7;
elessair 0:f269e3021894 131 break;
elessair 0:f269e3021894 132 case 8:
elessair 0:f269e3021894 133 sConfig.Channel = ADC_CHANNEL_8;
elessair 0:f269e3021894 134 break;
elessair 0:f269e3021894 135 case 9:
elessair 0:f269e3021894 136 sConfig.Channel = ADC_CHANNEL_9;
elessair 0:f269e3021894 137 break;
elessair 0:f269e3021894 138 case 10:
elessair 0:f269e3021894 139 sConfig.Channel = ADC_CHANNEL_10;
elessair 0:f269e3021894 140 break;
elessair 0:f269e3021894 141 case 11:
elessair 0:f269e3021894 142 sConfig.Channel = ADC_CHANNEL_11;
elessair 0:f269e3021894 143 break;
elessair 0:f269e3021894 144 case 12:
elessair 0:f269e3021894 145 sConfig.Channel = ADC_CHANNEL_12;
elessair 0:f269e3021894 146 break;
elessair 0:f269e3021894 147 case 13:
elessair 0:f269e3021894 148 sConfig.Channel = ADC_CHANNEL_13;
elessair 0:f269e3021894 149 break;
elessair 0:f269e3021894 150 case 14:
elessair 0:f269e3021894 151 sConfig.Channel = ADC_CHANNEL_14;
elessair 0:f269e3021894 152 break;
elessair 0:f269e3021894 153 case 15:
elessair 0:f269e3021894 154 sConfig.Channel = ADC_CHANNEL_15;
elessair 0:f269e3021894 155 break;
elessair 0:f269e3021894 156 case 16:
elessair 0:f269e3021894 157 sConfig.Channel = ADC_CHANNEL_TEMPSENSOR;
elessair 0:f269e3021894 158 break;
elessair 0:f269e3021894 159 case 17:
elessair 0:f269e3021894 160 sConfig.Channel = ADC_CHANNEL_VREFINT;
elessair 0:f269e3021894 161 break;
elessair 0:f269e3021894 162 #ifdef ADC_CHANNEL_VBAT
elessair 0:f269e3021894 163 case 18:
elessair 0:f269e3021894 164 sConfig.Channel = ADC_CHANNEL_VBAT;
elessair 0:f269e3021894 165 break;
elessair 0:f269e3021894 166 #endif
elessair 0:f269e3021894 167 default:
elessair 0:f269e3021894 168 return 0;
elessair 0:f269e3021894 169 }
elessair 0:f269e3021894 170
elessair 0:f269e3021894 171 // Clear all channels as it is not done in HAL_ADC_ConfigChannel()
elessair 0:f269e3021894 172 AdcHandle.Instance->CHSELR = 0;
elessair 0:f269e3021894 173
elessair 0:f269e3021894 174 HAL_ADC_ConfigChannel(&AdcHandle, &sConfig);
elessair 0:f269e3021894 175
elessair 0:f269e3021894 176 HAL_ADC_Start(&AdcHandle); // Start conversion
elessair 0:f269e3021894 177
elessair 0:f269e3021894 178 // Wait end of conversion and get value
elessair 0:f269e3021894 179 if (HAL_ADC_PollForConversion(&AdcHandle, 10) == HAL_OK) {
elessair 0:f269e3021894 180 return (HAL_ADC_GetValue(&AdcHandle));
elessair 0:f269e3021894 181 } else {
elessair 0:f269e3021894 182 return 0;
elessair 0:f269e3021894 183 }
elessair 0:f269e3021894 184 }
elessair 0:f269e3021894 185
elessair 0:f269e3021894 186 uint16_t analogin_read_u16(analogin_t *obj) {
elessair 0:f269e3021894 187 uint16_t value = adc_read(obj);
elessair 0:f269e3021894 188 // 12-bit to 16-bit conversion
elessair 0:f269e3021894 189 value = ((value << 4) & (uint16_t)0xFFF0) | ((value >> 8) & (uint16_t)0x000F);
elessair 0:f269e3021894 190 return value;
elessair 0:f269e3021894 191 }
elessair 0:f269e3021894 192
elessair 0:f269e3021894 193 float analogin_read(analogin_t *obj) {
elessair 0:f269e3021894 194 uint16_t value = adc_read(obj);
elessair 0:f269e3021894 195 return (float)value * (1.0f / (float)0xFFF); // 12 bits range
elessair 0:f269e3021894 196 }
elessair 0:f269e3021894 197
elessair 0:f269e3021894 198 #endif