mbed os with nrf51 internal bandgap enabled to read battery level
Dependents: BLE_file_test BLE_Blink ExternalEncoder
Diff: targets/TARGET_STM/TARGET_STM32F0/analogout_api.c
- Revision:
- 0:f269e3021894
--- /dev/null Thu Jan 01 00:00:00 1970 +0000 +++ b/targets/TARGET_STM/TARGET_STM32F0/analogout_api.c Sun Oct 23 15:10:02 2016 +0000 @@ -0,0 +1,138 @@ +/* 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 "analogout_api.h" + +#if DEVICE_ANALOGOUT + +#include "cmsis.h" +#include "pinmap.h" +#include "mbed_error.h" +#include "PeripheralPins.h" + +#define DAC_RANGE (0xFFF) // 12 bits +#define DAC_NB_BITS (12) + +static DAC_HandleTypeDef DacHandle; + +void analogout_init(dac_t *obj, PinName pin) { + DAC_ChannelConfTypeDef sConfig; + + // Get the peripheral name from the pin and assign it to the object + obj->dac = (DACName)pinmap_peripheral(pin, PinMap_DAC); + MBED_ASSERT(obj->dac != (DACName)NC); + + // Get the pin function and assign the used channel to the object + uint32_t function = pinmap_function(pin, PinMap_DAC); + MBED_ASSERT(function != (uint32_t)NC); + obj->channel = STM_PIN_CHANNEL(function); + + // Configure GPIO + pinmap_pinout(pin, PinMap_DAC); + + // Save the pin for future use + obj->pin = pin; + + // Enable DAC clock + __DAC1_CLK_ENABLE(); + + // Configure DAC + DacHandle.Instance = (DAC_TypeDef *)(obj->dac); + + sConfig.DAC_Trigger = DAC_TRIGGER_NONE; + sConfig.DAC_OutputBuffer = DAC_OUTPUTBUFFER_DISABLE; + + if (pin == PA_4) { + HAL_DAC_ConfigChannel(&DacHandle, &sConfig, DAC_CHANNEL_1); + } else { // PA_5 + HAL_DAC_ConfigChannel(&DacHandle, &sConfig, DAC_CHANNEL_2); + } + + analogout_write_u16(obj, 0); +} + +void analogout_free(dac_t *obj) { + // Reset DAC and disable clock + __DAC1_FORCE_RESET(); + __DAC1_RELEASE_RESET(); + __DAC1_CLK_DISABLE(); + + // Configure GPIO + pin_function(obj->pin, STM_PIN_DATA(STM_MODE_INPUT, GPIO_NOPULL, 0)); +} + +static inline void dac_write(dac_t *obj, int value) { + if (obj->channel == 1) { + HAL_DAC_SetValue(&DacHandle, DAC_CHANNEL_1, DAC_ALIGN_12B_R, (value & DAC_RANGE)); + HAL_DAC_Start(&DacHandle, DAC_CHANNEL_1); + } +#if defined(DAC_CHANNEL_2) + if (obj->channel == 2) { + HAL_DAC_SetValue(&DacHandle, DAC_CHANNEL_2, DAC_ALIGN_12B_R, (value & DAC_RANGE)); + HAL_DAC_Start(&DacHandle, DAC_CHANNEL_2); + } +#endif +} + +static inline int dac_read(dac_t *obj) { + if (obj->channel == 1) { + return (int)HAL_DAC_GetValue(&DacHandle, DAC_CHANNEL_1); + } +#if defined(DAC_CHANNEL_2) + if (obj->channel == 2) { + return (int)HAL_DAC_GetValue(&DacHandle, DAC_CHANNEL_2); + } +#endif + return 0; +} + +void analogout_write(dac_t *obj, float value) { + if (value < 0.0f) { + dac_write(obj, 0); // Min value + } else if (value > 1.0f) { + dac_write(obj, (int)DAC_RANGE); // Max value + } else { + dac_write(obj, (int)(value * (float)DAC_RANGE)); + } +} + +void analogout_write_u16(dac_t *obj, uint16_t value) { + dac_write(obj, value >> (16 - DAC_NB_BITS)); +} + +float analogout_read(dac_t *obj) { + uint32_t value = dac_read(obj); + return (float)value * (1.0f / (float)DAC_RANGE); +} + +uint16_t analogout_read_u16(dac_t *obj) { + uint32_t value = dac_read(obj); + return (value << 4) | ((value >> 8) & 0x000F); // Conversion from 12 to 16 bits +} + +#endif // DEVICE_ANALOGOUT