mbed library sources
Fork of mbed-src by
targets/hal/TARGET_STM/TARGET_NUCLEO_F103RB/analogin_api.c
- Committer:
- moirans2
- Date:
- 2015-01-14
- Revision:
- 445:9a3ffe6cfa19
- Parent:
- 414:4ec4c5b614b0
File content as of revision 445:9a3ffe6cfa19:
/* mbed Microcontroller Library * Copyright (c) 2014, STMicroelectronics * All rights reserved. * * Redistribution and use in source and binary forms, with or without * modification, are permitted provided that the following conditions are met: * * 1. Redistributions of source code must retain the above copyright notice, * this list of conditions and the following disclaimer. * 2. Redistributions in binary form must reproduce the above copyright notice, * this list of conditions and the following disclaimer in the documentation * and/or other materials provided with the distribution. * 3. Neither the name of STMicroelectronics nor the names of its contributors * may be used to endorse or promote products derived from this software * without specific prior written permission. * * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE * DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE LIABLE * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR * SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER * CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. */ #include "mbed_assert.h" #include "analogin_api.h" #if DEVICE_ANALOGIN #include "cmsis.h" #include "pinmap.h" #include "wait_api.h" #include "PeripheralPins.h" int adc_inited = 0; void analogin_init(analogin_t *obj, PinName pin) { ADC_TypeDef *adc; ADC_InitTypeDef ADC_InitStructure; // Get the peripheral name from the pin and assign it to the object obj->adc = (ADCName)pinmap_peripheral(pin, PinMap_ADC); MBED_ASSERT(obj->adc != (ADCName)NC); // Configure GPIO pinmap_pinout(pin, PinMap_ADC); // Save pin number for the read function obj->pin = pin; // The ADC initialization is done once if (adc_inited == 0) { adc_inited = 1; // Get ADC registers structure address adc = (ADC_TypeDef *)(obj->adc); // Enable ADC clock (14 MHz maximum) // PCLK2 = 64 MHz --> ADC clock = 64/6 = 10.666 MHz RCC_ADCCLKConfig(RCC_PCLK2_Div6); RCC_APB2PeriphClockCmd(RCC_APB2Periph_ADC1, ENABLE); // Configure ADC ADC_InitStructure.ADC_Mode = ADC_Mode_Independent; ADC_InitStructure.ADC_ScanConvMode = DISABLE; ADC_InitStructure.ADC_ContinuousConvMode = DISABLE; ADC_InitStructure.ADC_ExternalTrigConv = ADC_ExternalTrigConv_None; ADC_InitStructure.ADC_DataAlign = ADC_DataAlign_Right; ADC_InitStructure.ADC_NbrOfChannel = 1; ADC_Init(adc, &ADC_InitStructure); // Enable ADC ADC_Cmd(adc, ENABLE); // Calibrate ADC ADC_ResetCalibration(adc); while (ADC_GetResetCalibrationStatus(adc)); ADC_StartCalibration(adc); while (ADC_GetCalibrationStatus(adc)); } } static inline uint16_t adc_read(analogin_t *obj) { // Get ADC registers structure address ADC_TypeDef *adc = (ADC_TypeDef *)(obj->adc); int channel = 0; // Configure ADC channel switch (obj->pin) { case PA_0: channel = 0; break; case PA_1: channel = 1; break; case PA_2: channel = 2; break; case PA_3: channel = 3; break; case PA_4: channel = 4; break; case PA_5: channel = 5; break; case PA_6: channel = 6; break; case PA_7: channel = 7; break; case PB_0: channel = 8; break; case PB_1: channel = 9; break; case PC_0: channel = 10; break; case PC_1: channel = 11; break; case PC_2: channel = 12; break; case PC_3: channel = 13; break; case PC_4: channel = 14; break; case PC_5: channel = 15; break; default: return 0; } ADC_RegularChannelConfig(adc, channel, 1, ADC_SampleTime_7Cycles5); ADC_SoftwareStartConvCmd(adc, ENABLE); // Start conversion while (ADC_GetFlagStatus(adc, ADC_FLAG_EOC) == RESET); // Wait end of conversion return (ADC_GetConversionValue(adc)); // Get conversion value } uint16_t analogin_read_u16(analogin_t *obj) { uint16_t value = adc_read(obj); // 12-bit to 16-bit conversion value = ((value << 4) & (uint16_t)0xFFF0) | ((value >> 8) & (uint16_t)0x000F); return value; } float analogin_read(analogin_t *obj) { uint16_t value = adc_read(obj); return (float)value * (1.0f / (float)0xFFF); // 12 bits range } #endif