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Revision:
171:3a7713b1edbc
Parent:
169:a7c7b631e539
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/TARGET_TY51822R3/TOOLCHAIN_ARM_STD/app_pwm.h	Thu Nov 08 11:45:42 2018 +0000
@@ -0,0 +1,322 @@
+/* 
+ * Copyright (c) 2015 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 or object form under this license must not be reverse 
+ *      engineered, decompiled, modified and/or disassembled. 
+ * 
+ * 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.
+ * 
+ */
+
+
+/** @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_common.h"
+#include "nrf_drv_ppi.h"
+
+
+#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
+        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
+        nrf_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);
+/** @} */
+
+
+#endif
+
+/** @} */