Lee Kai Xuan
mbed-os
Fork of
mbed-os
by 
erkin yucel
Diff: targets/TARGET_STM/TARGET_STM32L4/analogin_api.c
- Revision:
- 0:f269e3021894
diff -r 000000000000 -r f269e3021894 targets/TARGET_STM/TARGET_STM32L4/analogin_api.c
--- /dev/null Thu Jan 01 00:00:00 1970 +0000
+++ b/targets/TARGET_STM/TARGET_STM32L4/analogin_api.c Sun Oct 23 15:10:02 2016 +0000
@@ -0,0 +1,197 @@
+/* mbed Microcontroller Library
+ * Copyright (c) 2016, 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;
+
+ // Enable ADC clock
+ __HAL_RCC_ADC_CLK_ENABLE();
+ __HAL_RCC_ADC_CONFIG(RCC_ADCCLKSOURCE_SYSCLK);
+
+ AdcHandle.Instance = (ADC_TypeDef *)(obj->adc);
+
+ // Configure ADC
+ AdcHandle.Init.ClockPrescaler = ADC_CLOCK_ASYNC_DIV2; // Asynchronous clock mode, input ADC clock
+ AdcHandle.Init.Resolution = ADC_RESOLUTION_12B;
+ AdcHandle.Init.DataAlign = ADC_DATAALIGN_RIGHT;
+ AdcHandle.Init.ScanConvMode = DISABLE; // Sequencer disabled (ADC conversion on only 1 channel: channel set on rank 1)
+ 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).
+ AdcHandle.Init.LowPowerAutoWait = DISABLE;
+ AdcHandle.Init.ContinuousConvMode = DISABLE; // Continuous mode disabled to have only 1 conversion at each conversion trig
+ AdcHandle.Init.NbrOfConversion = 1; // Parameter discarded because sequencer is disabled
+ AdcHandle.Init.DiscontinuousConvMode = DISABLE; // Parameter discarded because sequencer is disabled
+ AdcHandle.Init.NbrOfDiscConversion = 1; // Parameter discarded because sequencer is disabled
+ AdcHandle.Init.ExternalTrigConv = ADC_SOFTWARE_START; // Software start to trig the 1st conversion manually, without external event
+ AdcHandle.Init.ExternalTrigConvEdge = ADC_EXTERNALTRIGCONVEDGE_NONE;
+ AdcHandle.Init.DMAContinuousRequests = DISABLE;
+ AdcHandle.Init.Overrun = ADC_OVR_DATA_OVERWRITTEN; // DR register is overwritten with the last conversion result in case of overrun
+ AdcHandle.Init.OversamplingMode = DISABLE; // No oversampling
+
+ if (HAL_ADC_Init(&AdcHandle) != HAL_OK) {
+ error("Cannot initialize ADC\n");
+ }
+ }
+}
+
+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_VREFINT;
+ 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;
+ case 16:
+ sConfig.Channel = ADC_CHANNEL_16;
+ break;
+ case 17:
+ sConfig.Channel = ADC_CHANNEL_TEMPSENSOR;
+ break;
+ case 18:
+ sConfig.Channel = ADC_CHANNEL_VBAT;
+ break;
+ default:
+ return 0;
+ }
+
+ sConfig.Rank = ADC_REGULAR_RANK_1;
+ sConfig.SamplingTime = ADC_SAMPLETIME_47CYCLES_5;
+ sConfig.SingleDiff = ADC_SINGLE_ENDED;
+ sConfig.OffsetNumber = ADC_OFFSET_NONE;
+ sConfig.Offset = 0;
+
+ 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