spider-bot/fw/nrf52/nrf5_sdk/components/libraries/pwm/app_pwm.h

339 lines
13 KiB
C

/**
* Copyright (c) 2015 - 2019, Nordic Semiconductor ASA
*
* 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, except as embedded into a Nordic
* Semiconductor ASA integrated circuit in a product or a software update for
* such product, 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 Nordic Semiconductor ASA nor the names of its
* contributors may be used to endorse or promote products derived from this
* software without specific prior written permission.
*
* 4. This software, with or without modification, must only be used with a
* Nordic Semiconductor ASA integrated circuit.
*
* 5. Any software provided in binary form under this license must not be reverse
* engineered, decompiled, modified and/or disassembled.
*
* THIS SOFTWARE IS PROVIDED BY NORDIC SEMICONDUCTOR ASA "AS IS" AND ANY EXPRESS
* OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
* OF MERCHANTABILITY, NONINFRINGEMENT, AND FITNESS FOR A PARTICULAR PURPOSE ARE
* DISCLAIMED. IN NO EVENT SHALL NORDIC SEMICONDUCTOR ASA 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.
*
*/
/** @file
*
* @defgroup app_pwm Pulse-width modulation (PWM)
* @{
* @ingroup app_common
*
* @brief Module for generating a pulse-width modulated output signal.
*
* @details This module provides a PWM implementation using timers, GPIOTE, and PPI.
*
* Resource usage:
* - 2 PPI channels per instance + 2 PPI channels per PWM channel.
* - 1 PPI group per instance.
* - 1 GPIOTE channel per PWM channel.
*
* For example, a PWM instance with two channels will consume 2 + 4 PPI channels, 1 PPI group, and 2 GPIOTE channels.
*
* The maximum number of PWM channels per instance is 2.
*/
#ifndef APP_PWM_H__
#define APP_PWM_H__
#include <stdint.h>
#include "sdk_errors.h"
#include "nrf_drv_timer.h"
#include "nrf_drv_ppi.h"
#include "nrf_peripherals.h"
#ifdef __cplusplus
extern "C" {
#endif
#if defined(GPIOTE_FEATURE_SET_PRESENT) && defined(GPIOTE_FEATURE_CLR_PRESENT)
#define GPIOTE_SET_CLEAR_TASKS
#endif
#define APP_PWM_NOPIN 0xFFFFFFFF
/** @brief Number of channels for one timer instance (fixed to 2 due to timer properties).*/
#define APP_PWM_CHANNELS_PER_INSTANCE 2
/**@brief Macro for creating a PWM instance. */
#define APP_PWM_INSTANCE(name, num) \
const nrf_drv_timer_t m_pwm_##name##_timer = NRF_DRV_TIMER_INSTANCE(num); \
app_pwm_cb_t m_pwm_##name##_cb; \
/*lint -e{545}*/ \
const app_pwm_t name = { \
.p_cb = &m_pwm_##name##_cb, \
.p_timer = &m_pwm_##name##_timer, \
}
/**@brief PWM instance default configuration (1 channel). */
#define APP_PWM_DEFAULT_CONFIG_1CH(period_in_us, pin) \
{ \
.pins = {pin, APP_PWM_NOPIN}, \
.pin_polarity = {APP_PWM_POLARITY_ACTIVE_LOW, APP_PWM_POLARITY_ACTIVE_LOW}, \
.num_of_channels = 1, \
.period_us = period_in_us \
}
/**@brief PWM instance default configuration (2 channels). */
#define APP_PWM_DEFAULT_CONFIG_2CH(period_in_us, pin0, pin1) \
{ \
.pins = {pin0, pin1}, \
.pin_polarity = {APP_PWM_POLARITY_ACTIVE_LOW, APP_PWM_POLARITY_ACTIVE_LOW}, \
.num_of_channels = 2, \
.period_us = period_in_us \
}
typedef uint16_t app_pwm_duty_t;
/**
* @brief PWM callback that is executed when a PWM duty change has been completed.
*
* @param[in] pwm_id PWM instance ID.
*/
typedef void (* app_pwm_callback_t)(uint32_t);
/**
* @brief Channel polarity.
*/
typedef enum
{
APP_PWM_POLARITY_ACTIVE_LOW = 0,
APP_PWM_POLARITY_ACTIVE_HIGH = 1
} app_pwm_polarity_t;
/**@brief PWM configuration structure used for initialization. */
typedef struct
{
uint32_t pins[APP_PWM_CHANNELS_PER_INSTANCE]; //!< Pins configured as PWM output.
app_pwm_polarity_t pin_polarity[APP_PWM_CHANNELS_PER_INSTANCE]; //!< Polarity of active state on pin.
uint32_t num_of_channels; //!< Number of channels that can be used.
uint32_t period_us; //!< PWM signal output period to configure (in microseconds).
} app_pwm_config_t;
/**
* @cond (NODOX)
* @defgroup app_pwm_internal Auxiliary internal types declarations
* @{
* @internal
*
* @brief Module for internal usage inside the library only
*
* There are some definitions that must be included in the header file because
* of the way the library is set up. In this way, the are accessible to the user.
* However, any functions and variables defined here may change at any time
* without a warning, so you should not access them directly.
*/
/**
* @brief PWM channel instance
*
* This structure holds all data needed by a single PWM channel.
*/
typedef struct
{
uint32_t gpio_pin; //!< Pin that is used by this PWM channel.
uint32_t pulsewidth; //!< The copy of duty currently set (in ticks).
nrf_ppi_channel_t ppi_channels[2]; //!< PPI channels used by the PWM channel to clear and set the output.
app_pwm_polarity_t polarity; //!< The active state of the pin.
uint8_t initialized; //!< The internal information if the selected channel was initialized.
} app_pwm_channel_cb_t;
/**
* @brief Variable part of PWM instance
*
* This structure holds instance data that may change.
*/
typedef struct
{
app_pwm_channel_cb_t channels_cb[APP_PWM_CHANNELS_PER_INSTANCE]; //!< Channels data
uint32_t period; //!< Selected period in ticks
app_pwm_callback_t p_ready_callback; //!< Callback function called on PWM readiness
#ifdef GPIOTE_SET_CLEAR_TASKS
nrf_ppi_channel_t ppi_channel; //!< PPI channel used temporary while changing duty
#else
nrf_ppi_channel_t ppi_channels[2]; //!< PPI channels used temporary while changing duty
nrf_ppi_channel_group_t ppi_group; //!< PPI group used to synchronize changes on channels
#endif
nrfx_drv_state_t state; //!< Current driver status
} app_pwm_cb_t;
/** @}
* @endcond
*/
/**@brief PWM instance structure. */
typedef struct
{
app_pwm_cb_t *p_cb; //!< Pointer to control block internals.
nrf_drv_timer_t const * const p_timer; //!< Timer used by this PWM instance.
} app_pwm_t;
/**
* @brief Function for checking if the PWM instance is busy updating the duty cycle.
*
* @param[in] p_instance PWM instance.
*
* @retval True If the PWM instance is ready for duty cycle changes.
* @retval False If a change operation is in progress.
*/
bool app_pwm_busy_check(app_pwm_t const * const p_instance);
/**
* @brief Function for initializing a PWM instance.
*
* @param[in] p_instance PWM instance.
* @param[in] p_config Initial configuration.
* @param[in] p_ready_callback Pointer to ready callback function (or NULL to disable).
*
* @retval NRF_SUCCESS If initialization was successful.
* @retval NRF_ERROR_NO_MEM If there were not enough free resources.
* @retval NRF_ERROR_INVALID_PARAM If an invalid configuration structure was passed.
* @retval NRF_ERROR_INVALID_STATE If the timer/PWM is already in use or if initialization failed.
*/
ret_code_t app_pwm_init(app_pwm_t const * const p_instance, app_pwm_config_t const * const p_config,
app_pwm_callback_t p_ready_callback);
/**
* @brief Function for uninitializing a PWM instance and releasing the allocated resources.
*
* @param[in] p_instance PWM instance.
*
* @retval NRF_SUCCESS If uninitialization was successful.
* @retval NRF_ERROR_INVALID_STATE If the given instance was not initialized.
*/
ret_code_t app_pwm_uninit(app_pwm_t const * const p_instance);
/**
* @brief Function for enabling a PWM instance after initialization.
*
* @param[in] p_instance PWM instance.
*/
void app_pwm_enable(app_pwm_t const * const p_instance);
/**
* @brief Function for disabling a PWM instance after initialization.
*
* @param[in] p_instance PWM instance.
*/
void app_pwm_disable(app_pwm_t const * const p_instance);
/**
* @brief Function for setting the PWM channel duty cycle in percents.
*
* A duty cycle change requires one full PWM clock period to finish.
* If another change is attempted for any channel of given instance before
* the current change is complete, the new attempt will result in the error
* NRF_ERROR_BUSY.
*
* @param[in] p_instance PWM instance.
* @param[in] channel Channel number.
* @param[in] duty Duty cycle (0 - 100).
*
* @retval NRF_SUCCESS If the operation was successful.
* @retval NRF_ERROR_BUSY If the PWM is not ready yet.
* @retval NRF_ERROR_INVALID_STATE If the given instance was not initialized.
*
*/
ret_code_t app_pwm_channel_duty_set(app_pwm_t const * const p_instance,
uint8_t channel, app_pwm_duty_t duty);
/**
* @brief Function for retrieving the PWM channel duty cycle in percents.
*
* @param[in] p_instance PWM instance.
* @param[in] channel Channel number.
*
* @return Duty cycle value.
*/
app_pwm_duty_t app_pwm_channel_duty_get(app_pwm_t const * const p_instance, uint8_t channel);
/**
* @name Functions accessing values in ticks
*
* Auxiliary functions that allow to get values in actual timer ticks.
* @{
*/
/**
* @brief Function for setting PWM channel duty cycle in clock ticks.
*
* @note Duty cycle changes require one full PWM clock period to finish.
* Until that, the next change attempt (for any channel of given instance)
* will result in an NRF_ERROR_BUSY error.
*
* @param[in] p_instance PWM instance.
* @param[in] channel Channel number.
* @param[in] ticks Number of PWM clock ticks.
*
* @retval NRF_SUCCESS If the operation was successful.
* @retval NRF_ERROR_BUSY If PWM is not ready yet.
* @retval NRF_ERROR_INVALID_STATE If the given instance was not initialized.
*/
ret_code_t app_pwm_channel_duty_ticks_set(app_pwm_t const * const p_instance,
uint8_t channel,
uint16_t ticks);
/**
* @brief Function for retrieving the PWM channel duty cycle in ticks.
*
* This function retrieves the real, currently set duty cycle in ticks.
* For one full PWM cycle the value might be different than the value set by the last
* @ref app_pwm_channel_duty_ticks_set function call.
*
* @param[in] p_instance PWM instance.
* @param[in] channel Channel number.
*
* @return Number of ticks set for selected channel.
*
*/
uint16_t app_pwm_channel_duty_ticks_get(app_pwm_t const * const p_instance, uint8_t channel);
/**
* @brief Function for returning the number of ticks in a whole cycle.
*
* @param[in] p_instance PWM instance.
*
* @return Number of ticks that corresponds to 100% of the duty cycle.
*/
uint16_t app_pwm_cycle_ticks_get(app_pwm_t const * const p_instance);
/** @} */
#ifdef __cplusplus
}
#endif
#endif
/** @} */