tool/mbed/mbed-sdk/libraries/mbed/targets/hal/TARGET_STM/TARGET_STM32F3XX/analogout_api.c

   1 /* mbed Microcontroller Library
   2  * Copyright (c) 2014, STMicroelectronics
   3  * All rights reserved.
   4  *
   5  * Redistribution and use in source and binary forms, with or without
   6  * modification, are permitted provided that the following conditions are met:
   7  *
   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.
  16  *
  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.
  27  */
  28 #include "mbed_assert.h"
  29 #include "analogout_api.h"
  30
  31 #if DEVICE_ANALOGOUT
  32
  33 #include "cmsis.h"
  34 #include "pinmap.h"
  35
  36 #define RANGE_12BIT (0xFFF)
  37
  38 static const PinMap PinMap_DAC[] = {
  39     {PA_4, DAC_1, STM_PIN_DATA(GPIO_Mode_AN, GPIO_OType_PP, GPIO_PuPd_NOPULL, 0xFF)}, // DAC_OUT1
  40     {NC,   NC,    0}
  41 };
  42
  43 void analogout_init(dac_t *obj, PinName pin) {
  44     DAC_TypeDef *dac;
  45     DAC_InitTypeDef DAC_InitStructure;
  46
  47     // Get the peripheral name (DAC_1, ...) from the pin and assign it to the object
  48     obj->dac = (DACName)pinmap_peripheral(pin, PinMap_DAC);
  49     MBED_ASSERT(obj->dac == (DACName)NC);
  50
  51     dac = (DAC_TypeDef *)(obj->dac);
  52
  53     // Configure GPIO
  54     pinmap_pinout(pin, PinMap_DAC);
  55
  56     // Save the channel for the write and read functions
  57     obj->channel = pin;
  58
  59     // Enable DAC clock
  60     RCC_APB1PeriphClockCmd(RCC_APB1Periph_DAC, ENABLE);
  61
  62     // Configure and enable DAC channel
  63     DAC_StructInit(&DAC_InitStructure);
  64     DAC_Init(dac, DAC_Channel_1, &DAC_InitStructure);
  65     DAC_Cmd(dac, DAC_Channel_1, ENABLE);
  66
  67     analogout_write_u16(obj, 0);
  68 }
  69
  70 void analogout_free(dac_t *obj) {
  71 }
  72
  73 static inline void dac_write(dac_t *obj, uint16_t value) {
  74     DAC_TypeDef *dac = (DAC_TypeDef *)(obj->dac);
  75     DAC_SetChannel1Data(dac, DAC_Align_12b_R, value);
  76 }
  77
  78 static inline int dac_read(dac_t *obj) {
  79     DAC_TypeDef *dac = (DAC_TypeDef *)(obj->dac);
  80     return (int)DAC_GetDataOutputValue(dac, DAC_Channel_1);
  81 }
  82
  83 void analogout_write(dac_t *obj, float value) {
  84     if (value < 0.0f) {
  85         dac_write(obj, 0); // Min value
  86     } else if (value > 1.0f) {
  87         dac_write(obj, (uint16_t)RANGE_12BIT); // Max value
  88     } else {
  89         dac_write(obj, (uint16_t)(value * (float)RANGE_12BIT));
  90     }
  91 }
  92
  93 void analogout_write_u16(dac_t *obj, uint16_t value) {
  94     if (value > (uint16_t)RANGE_12BIT) {
  95         dac_write(obj, (uint16_t)RANGE_12BIT); // Max value
  96     } else {
  97         dac_write(obj, value);
  98     }
  99 }
 100
 101 float analogout_read(dac_t *obj) {
 102     uint32_t value = dac_read(obj);
 103     return (float)value * (1.0f / (float)RANGE_12BIT);
 104 }
 105
 106 uint16_t analogout_read_u16(dac_t *obj) {
 107     return (uint16_t)dac_read(obj);
 108 }
 109
 110 #endif // DEVICE_ANALOGOUT