1 /* mbed Microcontroller Library
2 * Copyright (c) 2014, STMicroelectronics
5 * Redistribution and use in source and binary forms, with or without
6 * modification, are permitted provided that the following conditions are met:
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.
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.
28 #include "mbed_assert.h"
29 #include "analogin_api.h"
36 #include "PeripheralPins.h"
38 ADC_HandleTypeDef AdcHandle;
42 void analogin_init(analogin_t *obj, PinName pin)
44 // Get the peripheral name from the pin and assign it to the object
45 obj->adc = (ADCName)pinmap_peripheral(pin, PinMap_ADC);
46 MBED_ASSERT(obj->adc != (ADCName)NC);
49 pinmap_pinout(pin, PinMap_ADC);
51 // Save pin number for the read function
54 // The ADC initialization is done once
55 if (adc_inited == 0) {
62 AdcHandle.Instance = (ADC_TypeDef *)(obj->adc);
63 AdcHandle.Init.ClockPrescaler = ADC_CLOCK_SYNC_PCLK_DIV4;
64 AdcHandle.Init.Resolution = ADC_RESOLUTION12b;
65 AdcHandle.Init.DataAlign = ADC_DATAALIGN_RIGHT;
66 AdcHandle.Init.ScanConvMode = DISABLE;
67 AdcHandle.Init.EOCSelection = EOC_SINGLE_CONV;
68 AdcHandle.Init.LowPowerAutoWait = DISABLE;
69 AdcHandle.Init.LowPowerAutoPowerOff = DISABLE;
70 AdcHandle.Init.ContinuousConvMode = DISABLE;
71 AdcHandle.Init.DiscontinuousConvMode = DISABLE;
72 AdcHandle.Init.ExternalTrigConv = ADC_SOFTWARE_START;
73 AdcHandle.Init.ExternalTrigConvEdge = ADC_EXTERNALTRIGCONVEDGE_NONE;
74 AdcHandle.Init.DMAContinuousRequests = DISABLE;
75 AdcHandle.Init.Overrun = OVR_DATA_OVERWRITTEN;
76 HAL_ADC_Init(&AdcHandle);
78 // Run the ADC calibration
79 HAL_ADCEx_Calibration_Start(&AdcHandle);
83 static inline uint16_t adc_read(analogin_t *obj)
85 ADC_ChannelConfTypeDef sConfig;
87 AdcHandle.Instance = (ADC_TypeDef *)(obj->adc);
89 // Configure ADC channel
90 sConfig.Rank = ADC_RANK_CHANNEL_NUMBER;
91 #if defined (TARGET_STM32F091RC)
92 sConfig.SamplingTime = ADC_SAMPLETIME_13CYCLES_5;
94 sConfig.SamplingTime = ADC_SAMPLETIME_7CYCLES_5;
99 sConfig.Channel = ADC_CHANNEL_0;
102 sConfig.Channel = ADC_CHANNEL_1;
105 sConfig.Channel = ADC_CHANNEL_2;
108 sConfig.Channel = ADC_CHANNEL_3;
111 sConfig.Channel = ADC_CHANNEL_4;
114 sConfig.Channel = ADC_CHANNEL_5;
117 sConfig.Channel = ADC_CHANNEL_6;
120 sConfig.Channel = ADC_CHANNEL_7;
123 sConfig.Channel = ADC_CHANNEL_8;
126 sConfig.Channel = ADC_CHANNEL_9;
129 sConfig.Channel = ADC_CHANNEL_10;
132 sConfig.Channel = ADC_CHANNEL_11;
135 sConfig.Channel = ADC_CHANNEL_12;
138 sConfig.Channel = ADC_CHANNEL_13;
141 sConfig.Channel = ADC_CHANNEL_14;
144 sConfig.Channel = ADC_CHANNEL_15;
150 // Clear all channels as it is not done in HAL_ADC_ConfigChannel()
151 AdcHandle.Instance->CHSELR = 0;
153 HAL_ADC_ConfigChannel(&AdcHandle, &sConfig);
155 HAL_ADC_Start(&AdcHandle); // Start conversion
157 // Wait end of conversion and get value
158 if (HAL_ADC_PollForConversion(&AdcHandle, 10) == HAL_OK) {
159 return (HAL_ADC_GetValue(&AdcHandle));
165 uint16_t analogin_read_u16(analogin_t *obj)
167 uint16_t value = adc_read(obj);
168 // 12-bit to 16-bit conversion
169 value = ((value << 4) & (uint16_t)0xFFF0) | ((value >> 8) & (uint16_t)0x000F);
173 float analogin_read(analogin_t *obj)
175 uint16_t value = adc_read(obj);
176 return (float)value * (1.0f / (float)0xFFF); // 12 bits range