erkin yucel / mbed-os

mbed os with nrf51 internal bandgap enabled to read battery level

Dependents:   BLE_file_test BLE_Blink ExternalEncoder

targets/TARGET_STM/TARGET_STM32L1/analogout_api.c@0:f269e3021894, 2016-10-23 (annotated)

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

Who changed what in which revision?

UserRevisionLine numberNew contents of line
elessair 0:f269e3021894 1 /* mbed Microcontroller Library
elessair 0:f269e3021894 2 * Copyright (c) 2014, 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 "analogout_api.h"
elessair 0:f269e3021894 30
elessair 0:f269e3021894 31 #if DEVICE_ANALOGOUT
elessair 0:f269e3021894 32
elessair 0:f269e3021894 33 #include "cmsis.h"
elessair 0:f269e3021894 34 #include "pinmap.h"
elessair 0:f269e3021894 35 #include "mbed_error.h"
elessair 0:f269e3021894 36 #include "PeripheralPins.h"
elessair 0:f269e3021894 37
elessair 0:f269e3021894 38 #define DAC_RANGE (0xFFF) // 12 bits
elessair 0:f269e3021894 39 #define DAC_NB_BITS (12)
elessair 0:f269e3021894 40
elessair 0:f269e3021894 41 static DAC_HandleTypeDef DacHandle;
elessair 0:f269e3021894 42
elessair 0:f269e3021894 43 // These variables are used for the "free" function
elessair 0:f269e3021894 44 static int pa4_used = 0;
elessair 0:f269e3021894 45 static int pa5_used = 0;
elessair 0:f269e3021894 46
elessair 0:f269e3021894 47 void analogout_init(dac_t *obj, PinName pin) {
elessair 0:f269e3021894 48 DAC_ChannelConfTypeDef sConfig;
elessair 0:f269e3021894 49
elessair 0:f269e3021894 50 DacHandle.Instance = DAC;
elessair 0:f269e3021894 51
elessair 0:f269e3021894 52 // Get the peripheral name (DAC_1, ...) from the pin and assign it to the object
elessair 0:f269e3021894 53 obj->dac = (DACName)pinmap_peripheral(pin, PinMap_DAC);
elessair 0:f269e3021894 54 MBED_ASSERT(obj->dac != (DACName)NC);
elessair 0:f269e3021894 55
elessair 0:f269e3021894 56 // Configure GPIO
elessair 0:f269e3021894 57 pinmap_pinout(pin, PinMap_DAC);
elessair 0:f269e3021894 58
elessair 0:f269e3021894 59 // Save the channel for future use
elessair 0:f269e3021894 60 obj->pin = pin;
elessair 0:f269e3021894 61
elessair 0:f269e3021894 62 // Enable DAC clock
elessair 0:f269e3021894 63 __DAC_CLK_ENABLE();
elessair 0:f269e3021894 64
elessair 0:f269e3021894 65 // Configure DAC
elessair 0:f269e3021894 66 sConfig.DAC_Trigger = DAC_TRIGGER_NONE;
elessair 0:f269e3021894 67 sConfig.DAC_OutputBuffer = DAC_OUTPUTBUFFER_DISABLE;
elessair 0:f269e3021894 68
elessair 0:f269e3021894 69 if (pin == PA_4) {
elessair 0:f269e3021894 70 HAL_DAC_ConfigChannel(&DacHandle, &sConfig, DAC_CHANNEL_1);
elessair 0:f269e3021894 71 pa4_used = 1;
elessair 0:f269e3021894 72 } else { // PA_5
elessair 0:f269e3021894 73 HAL_DAC_ConfigChannel(&DacHandle, &sConfig, DAC_CHANNEL_2);
elessair 0:f269e3021894 74 pa5_used = 1;
elessair 0:f269e3021894 75 }
elessair 0:f269e3021894 76
elessair 0:f269e3021894 77 analogout_write_u16(obj, 0);
elessair 0:f269e3021894 78 }
elessair 0:f269e3021894 79
elessair 0:f269e3021894 80 void analogout_free(dac_t *obj) {
elessair 0:f269e3021894 81 // Reset DAC and disable clock
elessair 0:f269e3021894 82 if (obj->pin == PA_4) pa4_used = 0;
elessair 0:f269e3021894 83 if (obj->pin == PA_5) pa5_used = 0;
elessair 0:f269e3021894 84 if ((pa4_used == 0) && (pa5_used == 0)) {
elessair 0:f269e3021894 85 __DAC_FORCE_RESET();
elessair 0:f269e3021894 86 __DAC_RELEASE_RESET();
elessair 0:f269e3021894 87 __DAC_CLK_DISABLE();
elessair 0:f269e3021894 88 }
elessair 0:f269e3021894 89
elessair 0:f269e3021894 90 // Configure GPIO
elessair 0:f269e3021894 91 pin_function(obj->pin, STM_PIN_DATA(STM_MODE_INPUT, GPIO_NOPULL, 0));
elessair 0:f269e3021894 92 }
elessair 0:f269e3021894 93
elessair 0:f269e3021894 94 static inline void dac_write(dac_t *obj, int value) {
elessair 0:f269e3021894 95 if (obj->pin == PA_4) {
elessair 0:f269e3021894 96 HAL_DAC_SetValue(&DacHandle, DAC_CHANNEL_1, DAC_ALIGN_12B_R, (value & DAC_RANGE));
elessair 0:f269e3021894 97 HAL_DAC_Start(&DacHandle, DAC_CHANNEL_1);
elessair 0:f269e3021894 98 } else { // PA_5
elessair 0:f269e3021894 99 HAL_DAC_SetValue(&DacHandle, DAC_CHANNEL_2, DAC_ALIGN_12B_R, (value & DAC_RANGE));
elessair 0:f269e3021894 100 HAL_DAC_Start(&DacHandle, DAC_CHANNEL_2);
elessair 0:f269e3021894 101 }
elessair 0:f269e3021894 102 }
elessair 0:f269e3021894 103
elessair 0:f269e3021894 104 static inline int dac_read(dac_t *obj) {
elessair 0:f269e3021894 105 if (obj->pin == PA_4) {
elessair 0:f269e3021894 106 return (int)HAL_DAC_GetValue(&DacHandle, DAC_CHANNEL_1);
elessair 0:f269e3021894 107 } else { // PA_5
elessair 0:f269e3021894 108 return (int)HAL_DAC_GetValue(&DacHandle, DAC_CHANNEL_2);
elessair 0:f269e3021894 109 }
elessair 0:f269e3021894 110 }
elessair 0:f269e3021894 111
elessair 0:f269e3021894 112 void analogout_write(dac_t *obj, float value) {
elessair 0:f269e3021894 113 if (value < 0.0f) {
elessair 0:f269e3021894 114 dac_write(obj, 0); // Min value
elessair 0:f269e3021894 115 } else if (value > 1.0f) {
elessair 0:f269e3021894 116 dac_write(obj, (int)DAC_RANGE); // Max value
elessair 0:f269e3021894 117 } else {
elessair 0:f269e3021894 118 dac_write(obj, (int)(value * (float)DAC_RANGE));
elessair 0:f269e3021894 119 }
elessair 0:f269e3021894 120 }
elessair 0:f269e3021894 121
elessair 0:f269e3021894 122 void analogout_write_u16(dac_t *obj, uint16_t value) {
elessair 0:f269e3021894 123 dac_write(obj, value >> (16 - DAC_NB_BITS));
elessair 0:f269e3021894 124 }
elessair 0:f269e3021894 125
elessair 0:f269e3021894 126 float analogout_read(dac_t *obj) {
elessair 0:f269e3021894 127 uint32_t value = dac_read(obj);
elessair 0:f269e3021894 128 return (float)value * (1.0f / (float)DAC_RANGE);
elessair 0:f269e3021894 129 }
elessair 0:f269e3021894 130
elessair 0:f269e3021894 131 uint16_t analogout_read_u16(dac_t *obj) {
elessair 0:f269e3021894 132 uint32_t value = dac_read(obj);
elessair 0:f269e3021894 133 return (value << 4) | ((value >> 8) & 0x000F); // Conversion from 12 to 16 bits
elessair 0:f269e3021894 134 }
elessair 0:f269e3021894 135
elessair 0:f269e3021894 136 #endif // DEVICE_ANALOGOUT