esp-idf/components/driver/include/driver/sigmadelta.h

110 lines
3.7 KiB
C

// Copyright 2015-2016 Espressif Systems (Shanghai) PTE LTD
//
// Licensed under the Apache License, Version 2.0 (the "License");
// you may not use this file except in compliance with the License.
// You may obtain a copy of the License at
// http://www.apache.org/licenses/LICENSE-2.0
//
// Unless required by applicable law or agreed to in writing, software
// distributed under the License is distributed on an "AS IS" BASIS,
// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
// See the License for the specific language governing permissions and
// limitations under the License.
#ifndef __DRIVER_SIGMADELTA_H__
#define __DRIVER_SIGMADELTA_H__
#include <esp_types.h>
#include "soc/gpio_sd_struct.h"
#include "soc/gpio_sd_reg.h"
#include "driver/gpio.h"
#ifdef _cplusplus
extern "C" {
#endif
/**
* @brief Sigma-delta channel list
*/
typedef enum{
SIGMADELTA_CHANNEL_0 = 0, /*!< Sigma-delta channel 0 */
SIGMADELTA_CHANNEL_1 = 1, /*!< Sigma-delta channel 1 */
SIGMADELTA_CHANNEL_2 = 2, /*!< Sigma-delta channel 2 */
SIGMADELTA_CHANNEL_3 = 3, /*!< Sigma-delta channel 3 */
SIGMADELTA_CHANNEL_4 = 4, /*!< Sigma-delta channel 4 */
SIGMADELTA_CHANNEL_5 = 5, /*!< Sigma-delta channel 5 */
SIGMADELTA_CHANNEL_6 = 6, /*!< Sigma-delta channel 6 */
SIGMADELTA_CHANNEL_7 = 7, /*!< Sigma-delta channel 7 */
SIGMADELTA_CHANNEL_MAX,
} sigmadelta_channel_t;
/**
* @brief Sigma-delta configure struct
*/
typedef struct {
sigmadelta_channel_t channel; /*!< Sigma-delta channel number */
int8_t sigmadelta_duty; /*!< Sigma-delta duty, duty ranges from -128 to 127. */
uint8_t sigmadelta_prescale; /*!< Sigma-delta prescale, prescale ranges from 0 to 255. */
uint8_t sigmadelta_gpio; /*!< Sigma-delta output io number, refer to gpio.h for more details. */
} sigmadelta_config_t;
/**
* @brief Configure Sigma-delta channel
*
* @param config Pointer of Sigma-delta channel configuration struct
*
* @return
* - ESP_OK Success
* - ESP_ERR_INVALID_ARG Parameter error
*/
esp_err_t sigmadelta_config(const sigmadelta_config_t *config);
/**
* @brief Set Sigma-delta channel duty.
*
* This function is used to set Sigma-delta channel duty,
* If you add a capacitor between the output pin and ground,
* the average output voltage will be Vdc = VDDIO / 256 * duty + VDDIO/2,
* where VDDIO is the power supply voltage.
*
* @param channel Sigma-delta channel number
* @param duty Sigma-delta duty of one channel, the value ranges from -128 to 127, recommended range is -90 ~ 90.
* The waveform is more like a random one in this range.
*
* @return
* - ESP_OK Success
* - ESP_ERR_INVALID_ARG Parameter error
*/
esp_err_t sigmadelta_set_duty(sigmadelta_channel_t channel, int8_t duty);
/**
* @brief Set Sigma-delta channel's clock pre-scale value.
* The source clock is APP_CLK, 80MHz. The clock frequency of the sigma-delta channel is APP_CLK / pre_scale
*
* @param channel Sigma-delta channel number
* @param prescale The divider of source clock, ranges from 0 to 255
*
* @return
* - ESP_OK Success
* - ESP_ERR_INVALID_ARG Parameter error
*/
esp_err_t sigmadelta_set_prescale(sigmadelta_channel_t channel, uint8_t prescale);
/**
* @brief Set Sigma-delta signal output pin
*
* @param channel Sigma-delta channel number
* @param gpio_num GPIO number of output pin.
*
* @return
* - ESP_OK Success
* - ESP_ERR_INVALID_ARG Parameter error
*/
esp_err_t sigmadelta_set_pin(sigmadelta_channel_t channel, gpio_num_t gpio_num);
#ifdef _cplusplus
}
#endif
#endif