mbed os with nrf51 internal bandgap enabled to read battery level
Dependents: BLE_file_test BLE_Blink ExternalEncoder
Diff: targets/TARGET_STM/TARGET_STM32L0/analogin_api.c
- Revision:
- 0:f269e3021894
diff -r 000000000000 -r f269e3021894 targets/TARGET_STM/TARGET_STM32L0/analogin_api.c --- /dev/null Thu Jan 01 00:00:00 1970 +0000 +++ b/targets/TARGET_STM/TARGET_STM32L0/analogin_api.c Sun Oct 23 15:10:02 2016 +0000 @@ -0,0 +1,199 @@ +/* mbed Microcontroller Library + * Copyright (c) 2015, 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 "wait_api.h" +#include "cmsis.h" +#include "pinmap.h" +#include "mbed_error.h" +#include "PeripheralPins.h" + +ADC_HandleTypeDef AdcHandle; + +int adc_inited = 0; + +void analogin_init(analogin_t *obj, PinName pin) +{ + // 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); + + // Get the pin function and assign the used channel to the object + uint32_t function = pinmap_function(pin, PinMap_ADC); + MBED_ASSERT(function != (uint32_t)NC); + obj->channel = STM_PIN_CHANNEL(function); + + // Configure GPIO excepted for internal channels (Temperature, Vref, Vbat, ...) + // ADC Internal Channels "pins" are described in PinNames.h and must have a value >= 0xF0 + if (pin < 0xF0) { + 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; + + AdcHandle.Instance = (ADC_TypeDef *)(obj->adc); + + // Enable ADC clock + __ADC1_CLK_ENABLE(); + + // Configure ADC + AdcHandle.Init.OversamplingMode = DISABLE; + AdcHandle.Init.ClockPrescaler = ADC_CLOCKPRESCALER_PCLK_DIV1; + AdcHandle.Init.Resolution = ADC_RESOLUTION12b; + AdcHandle.Init.SamplingTime = ADC_SAMPLETIME_41CYCLES_5; + AdcHandle.Init.ScanConvMode = ADC_SCAN_DIRECTION_FORWARD; + AdcHandle.Init.DataAlign = ADC_DATAALIGN_RIGHT; + AdcHandle.Init.ContinuousConvMode = DISABLE; + AdcHandle.Init.DiscontinuousConvMode = DISABLE; + AdcHandle.Init.ExternalTrigConvEdge = ADC_EXTERNALTRIG_EDGE_NONE; + AdcHandle.Init.ExternalTrigConv = ADC_EXTERNALTRIG0_T6_TRGO; // Not used here + AdcHandle.Init.DMAContinuousRequests = DISABLE; + AdcHandle.Init.EOCSelection = EOC_SINGLE_CONV; + AdcHandle.Init.Overrun = OVR_DATA_OVERWRITTEN; + AdcHandle.Init.LowPowerAutoWait = ENABLE; + AdcHandle.Init.LowPowerFrequencyMode = DISABLE; // To be enabled only if ADC clock < 2.8 MHz + AdcHandle.Init.LowPowerAutoPowerOff = DISABLE; + + if (HAL_ADC_Init(&AdcHandle) != HAL_OK) { + error("Cannot initialize ADC"); + } + + // Calibration + HAL_ADCEx_Calibration_Start(&AdcHandle, ADC_SINGLE_ENDED); + + __HAL_ADC_ENABLE(&AdcHandle); + } +} + +static inline uint16_t adc_read(analogin_t *obj) +{ + ADC_ChannelConfTypeDef sConfig = {0}; + + AdcHandle.Instance = (ADC_TypeDef *)(obj->adc); + + // Configure ADC channel + switch (obj->channel) { + case 0: + sConfig.Channel = ADC_CHANNEL_0; + break; + case 1: + sConfig.Channel = ADC_CHANNEL_1; + break; + case 2: + sConfig.Channel = ADC_CHANNEL_2; + break; + case 3: + sConfig.Channel = ADC_CHANNEL_3; + break; + case 4: + sConfig.Channel = ADC_CHANNEL_4; + break; + case 5: + sConfig.Channel = ADC_CHANNEL_5; + break; + case 6: + sConfig.Channel = ADC_CHANNEL_6; + break; + case 7: + sConfig.Channel = ADC_CHANNEL_7; + break; + case 8: + sConfig.Channel = ADC_CHANNEL_8; + break; + case 9: + sConfig.Channel = ADC_CHANNEL_9; + break; + case 10: + sConfig.Channel = ADC_CHANNEL_10; + break; + case 11: + sConfig.Channel = ADC_CHANNEL_11; + break; + case 12: + sConfig.Channel = ADC_CHANNEL_12; + break; + case 13: + sConfig.Channel = ADC_CHANNEL_13; + break; + case 14: + sConfig.Channel = ADC_CHANNEL_14; + break; + case 15: + sConfig.Channel = ADC_CHANNEL_15; + break; +#ifdef ADC_CHANNEL_VLCD + case 16: + sConfig.Channel = ADC_CHANNEL_VLCD; + break; +#endif + case 17: + sConfig.Channel = ADC_CHANNEL_VREFINT; + break; + case 18: + sConfig.Channel = ADC_CHANNEL_TEMPSENSOR; + break; + default: + return 0; + } + + ADC1->CHSELR = 0; // [TODO] Workaround. To be removed after Cube driver is corrected. + HAL_ADC_ConfigChannel(&AdcHandle, &sConfig); + + HAL_ADC_Start(&AdcHandle); // Start conversion + + // Wait end of conversion and get value + if (HAL_ADC_PollForConversion(&AdcHandle, 10) == HAL_OK) { + return (HAL_ADC_GetValue(&AdcHandle)); + } else { + return 0; + } +} + +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