mbed official / mbed

The official Mbed 2 C/C++ SDK provides the software platform and libraries to build your applications.

Dependents:   hello SerialTestv11 SerialTestv12 Sierpinski ... more

mbed 2

This is the mbed 2 library. If you'd like to learn about Mbed OS please see the mbed-os docs.

hal/ticker_api.h@170:e95d10626187, 2018-09-06 (annotated)

Committer:
AnnaBridge
Date:
Thu Sep 06 13:39:34 2018 +0100
Revision:
170:e95d10626187
Parent:
169:a7c7b631e539
Child:
171:3a7713b1edbc
mbed library. Release version 163

Who changed what in which revision?

UserRevisionLine numberNew contents of line
AnnaBridge 156:ff21514d8981 1
AnnaBridge 156:ff21514d8981 2 /** \addtogroup hal */
AnnaBridge 156:ff21514d8981 3 /** @{*/
AnnaBridge 156:ff21514d8981 4 /* mbed Microcontroller Library
AnnaBridge 156:ff21514d8981 5 * Copyright (c) 2015 ARM Limited
AnnaBridge 156:ff21514d8981 6 *
AnnaBridge 156:ff21514d8981 7 * Licensed under the Apache License, Version 2.0 (the "License");
AnnaBridge 156:ff21514d8981 8 * you may not use this file except in compliance with the License.
AnnaBridge 156:ff21514d8981 9 * You may obtain a copy of the License at
AnnaBridge 156:ff21514d8981 10 *
AnnaBridge 156:ff21514d8981 11 * http://www.apache.org/licenses/LICENSE-2.0
AnnaBridge 156:ff21514d8981 12 *
AnnaBridge 156:ff21514d8981 13 * Unless required by applicable law or agreed to in writing, software
AnnaBridge 156:ff21514d8981 14 * distributed under the License is distributed on an "AS IS" BASIS,
AnnaBridge 156:ff21514d8981 15 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
AnnaBridge 156:ff21514d8981 16 * See the License for the specific language governing permissions and
AnnaBridge 156:ff21514d8981 17 * limitations under the License.
AnnaBridge 156:ff21514d8981 18 */
AnnaBridge 156:ff21514d8981 19 #ifndef MBED_TICKER_API_H
AnnaBridge 156:ff21514d8981 20 #define MBED_TICKER_API_H
AnnaBridge 156:ff21514d8981 21
AnnaBridge 156:ff21514d8981 22 #include <stdint.h>
AnnaBridge 156:ff21514d8981 23 #include <stdbool.h>
AnnaBridge 156:ff21514d8981 24 #include "device.h"
AnnaBridge 156:ff21514d8981 25
AnnaBridge 156:ff21514d8981 26 /**
AnnaBridge 156:ff21514d8981 27 * Legacy format representing a timestamp in us.
AnnaBridge 156:ff21514d8981 28 * Given it is modeled as a 32 bit integer, this type can represent timestamp
AnnaBridge 156:ff21514d8981 29 * up to 4294 seconds (71 minutes).
AnnaBridge 156:ff21514d8981 30 * Prefer using us_timestamp_t which store timestamp as 64 bits integer.
AnnaBridge 156:ff21514d8981 31 */
AnnaBridge 156:ff21514d8981 32 typedef uint32_t timestamp_t;
AnnaBridge 156:ff21514d8981 33
AnnaBridge 156:ff21514d8981 34 /**
AnnaBridge 156:ff21514d8981 35 * A us timestamp stored in a 64 bit integer.
AnnaBridge 156:ff21514d8981 36 * Can store timestamp up to 584810 years.
AnnaBridge 156:ff21514d8981 37 */
AnnaBridge 156:ff21514d8981 38 typedef uint64_t us_timestamp_t;
AnnaBridge 156:ff21514d8981 39
AnnaBridge 156:ff21514d8981 40 /** Ticker's event structure
AnnaBridge 156:ff21514d8981 41 */
AnnaBridge 156:ff21514d8981 42 typedef struct ticker_event_s {
AnnaBridge 156:ff21514d8981 43 us_timestamp_t timestamp; /**< Event's timestamp */
AnnaBridge 156:ff21514d8981 44 uint32_t id; /**< TimerEvent object */
AnnaBridge 156:ff21514d8981 45 struct ticker_event_s *next; /**< Next event in the queue */
AnnaBridge 156:ff21514d8981 46 } ticker_event_t;
AnnaBridge 156:ff21514d8981 47
AnnaBridge 156:ff21514d8981 48 typedef void (*ticker_event_handler)(uint32_t id);
AnnaBridge 156:ff21514d8981 49
Anna Bridge 160:5571c4ff569f 50 /** Information about the ticker implementation
Anna Bridge 160:5571c4ff569f 51 */
Anna Bridge 160:5571c4ff569f 52 typedef struct {
Anna Bridge 160:5571c4ff569f 53 uint32_t frequency; /**< Frequency in Hz this ticker runs at */
Anna Bridge 160:5571c4ff569f 54 uint32_t bits; /**< Number of bits this ticker supports */
Anna Bridge 160:5571c4ff569f 55 } ticker_info_t;
Anna Bridge 160:5571c4ff569f 56
Anna Bridge 160:5571c4ff569f 57
AnnaBridge 156:ff21514d8981 58 /** Ticker's interface structure - required API for a ticker
AnnaBridge 156:ff21514d8981 59 */
AnnaBridge 156:ff21514d8981 60 typedef struct {
AnnaBridge 156:ff21514d8981 61 void (*init)(void); /**< Init function */
AnnaBridge 156:ff21514d8981 62 uint32_t (*read)(void); /**< Read function */
AnnaBridge 156:ff21514d8981 63 void (*disable_interrupt)(void); /**< Disable interrupt function */
AnnaBridge 156:ff21514d8981 64 void (*clear_interrupt)(void); /**< Clear interrupt function */
AnnaBridge 156:ff21514d8981 65 void (*set_interrupt)(timestamp_t timestamp); /**< Set interrupt function */
AnnaBridge 156:ff21514d8981 66 void (*fire_interrupt)(void); /**< Fire interrupt right-away */
Anna Bridge 160:5571c4ff569f 67 const ticker_info_t *(*get_info)(void); /**< Return info about this ticker's implementation */
AnnaBridge 156:ff21514d8981 68 } ticker_interface_t;
AnnaBridge 156:ff21514d8981 69
AnnaBridge 156:ff21514d8981 70 /** Ticker's event queue structure
AnnaBridge 156:ff21514d8981 71 */
AnnaBridge 156:ff21514d8981 72 typedef struct {
AnnaBridge 156:ff21514d8981 73 ticker_event_handler event_handler; /**< Event handler */
AnnaBridge 156:ff21514d8981 74 ticker_event_t *head; /**< A pointer to head */
Anna Bridge 160:5571c4ff569f 75 uint32_t frequency; /**< Frequency of the timer in Hz */
Anna Bridge 160:5571c4ff569f 76 uint32_t bitmask; /**< Mask to be applied to time values read */
Anna Bridge 160:5571c4ff569f 77 uint32_t max_delta; /**< Largest delta in ticks that can be used when scheduling */
Anna Bridge 160:5571c4ff569f 78 uint64_t max_delta_us; /**< Largest delta in us that can be used when scheduling */
Anna Bridge 160:5571c4ff569f 79 uint32_t tick_last_read; /**< Last tick read */
Anna Bridge 160:5571c4ff569f 80 uint64_t tick_remainder; /**< Ticks that have not been added to base_time */
AnnaBridge 156:ff21514d8981 81 us_timestamp_t present_time; /**< Store the timestamp used for present time */
AnnaBridge 156:ff21514d8981 82 bool initialized; /**< Indicate if the instance is initialized */
AnnaBridge 170:e95d10626187 83 bool dispatching; /**< The function ticker_irq_handler is dispatching */
AnnaBridge 170:e95d10626187 84 uint8_t frequency_shifts; /**< If frequency is a value of 2^n, this is n, otherwise 0 */
AnnaBridge 156:ff21514d8981 85 } ticker_event_queue_t;
AnnaBridge 156:ff21514d8981 86
AnnaBridge 156:ff21514d8981 87 /** Ticker's data structure
AnnaBridge 156:ff21514d8981 88 */
AnnaBridge 156:ff21514d8981 89 typedef struct {
AnnaBridge 156:ff21514d8981 90 const ticker_interface_t *interface; /**< Ticker's interface */
AnnaBridge 156:ff21514d8981 91 ticker_event_queue_t *queue; /**< Ticker's event queue */
AnnaBridge 156:ff21514d8981 92 } ticker_data_t;
AnnaBridge 156:ff21514d8981 93
AnnaBridge 156:ff21514d8981 94 #ifdef __cplusplus
AnnaBridge 156:ff21514d8981 95 extern "C" {
AnnaBridge 156:ff21514d8981 96 #endif
AnnaBridge 156:ff21514d8981 97
AnnaBridge 156:ff21514d8981 98 /**
AnnaBridge 156:ff21514d8981 99 * \defgroup hal_ticker Ticker HAL functions
AnnaBridge 156:ff21514d8981 100 * @{
AnnaBridge 156:ff21514d8981 101 */
AnnaBridge 156:ff21514d8981 102
AnnaBridge 156:ff21514d8981 103 /** Initialize a ticker and set the event handler
AnnaBridge 156:ff21514d8981 104 *
AnnaBridge 156:ff21514d8981 105 * @param ticker The ticker object.
AnnaBridge 156:ff21514d8981 106 * @param handler A handler to be set
AnnaBridge 156:ff21514d8981 107 */
AnnaBridge 156:ff21514d8981 108 void ticker_set_handler(const ticker_data_t *const ticker, ticker_event_handler handler);
AnnaBridge 156:ff21514d8981 109
AnnaBridge 156:ff21514d8981 110 /** IRQ handler that goes through the events to trigger overdue events.
AnnaBridge 156:ff21514d8981 111 *
AnnaBridge 156:ff21514d8981 112 * @param ticker The ticker object.
AnnaBridge 156:ff21514d8981 113 */
AnnaBridge 156:ff21514d8981 114 void ticker_irq_handler(const ticker_data_t *const ticker);
AnnaBridge 156:ff21514d8981 115
AnnaBridge 156:ff21514d8981 116 /** Remove an event from the queue
AnnaBridge 156:ff21514d8981 117 *
AnnaBridge 156:ff21514d8981 118 * @param ticker The ticker object.
AnnaBridge 156:ff21514d8981 119 * @param obj The event object to be removed from the queue
AnnaBridge 156:ff21514d8981 120 */
AnnaBridge 156:ff21514d8981 121 void ticker_remove_event(const ticker_data_t *const ticker, ticker_event_t *obj);
AnnaBridge 156:ff21514d8981 122
AnnaBridge 156:ff21514d8981 123 /** Insert an event to the queue
AnnaBridge 156:ff21514d8981 124 *
AnnaBridge 156:ff21514d8981 125 * The event will be executed in timestamp - ticker_read().
AnnaBridge 156:ff21514d8981 126 *
AnnaBridge 156:ff21514d8981 127 * @warning This function does not consider timestamp in the past. If an event
AnnaBridge 156:ff21514d8981 128 * is inserted with a timestamp less than the current timestamp then the event
AnnaBridge 156:ff21514d8981 129 * will be executed in timestamp - ticker_read() us.
AnnaBridge 156:ff21514d8981 130 * The internal counter wrap very quickly it is hard to decide weither an
AnnaBridge 156:ff21514d8981 131 * event is in the past or in 1 hour.
AnnaBridge 156:ff21514d8981 132 *
AnnaBridge 156:ff21514d8981 133 * @note prefer the use of ticker_insert_event_us which allows registration of
AnnaBridge 156:ff21514d8981 134 * absolute timestamp.
AnnaBridge 156:ff21514d8981 135 *
AnnaBridge 156:ff21514d8981 136 * @param ticker The ticker object.
AnnaBridge 156:ff21514d8981 137 * @param obj The event object to be inserted to the queue
AnnaBridge 156:ff21514d8981 138 * @param timestamp The event's timestamp
AnnaBridge 156:ff21514d8981 139 * @param id The event object
AnnaBridge 156:ff21514d8981 140 */
AnnaBridge 156:ff21514d8981 141 void ticker_insert_event(const ticker_data_t *const ticker, ticker_event_t *obj, timestamp_t timestamp, uint32_t id);
AnnaBridge 156:ff21514d8981 142
AnnaBridge 156:ff21514d8981 143 /** Insert an event to the queue
AnnaBridge 156:ff21514d8981 144 *
AnnaBridge 156:ff21514d8981 145 * The event will be executed in timestamp - ticker_read_us() us.
AnnaBridge 156:ff21514d8981 146 *
AnnaBridge 156:ff21514d8981 147 * @note If an event is inserted with a timestamp less than the current
AnnaBridge 156:ff21514d8981 148 * timestamp then the event will be scheduled immediately resulting in
AnnaBridge 156:ff21514d8981 149 * an instant call to event handler.
AnnaBridge 156:ff21514d8981 150 *
AnnaBridge 156:ff21514d8981 151 * @param ticker The ticker object.
AnnaBridge 156:ff21514d8981 152 * @param obj The event object to be inserted to the queue
AnnaBridge 156:ff21514d8981 153 * @param timestamp The event's timestamp
AnnaBridge 156:ff21514d8981 154 * @param id The event object
AnnaBridge 156:ff21514d8981 155 */
AnnaBridge 156:ff21514d8981 156 void ticker_insert_event_us(const ticker_data_t *const ticker, ticker_event_t *obj, us_timestamp_t timestamp, uint32_t id);
AnnaBridge 156:ff21514d8981 157
AnnaBridge 156:ff21514d8981 158 /** Read the current (relative) ticker's timestamp
AnnaBridge 156:ff21514d8981 159 *
AnnaBridge 156:ff21514d8981 160 * @warning Return a relative timestamp because the counter wrap every 4294
AnnaBridge 156:ff21514d8981 161 * seconds.
AnnaBridge 156:ff21514d8981 162 *
AnnaBridge 156:ff21514d8981 163 * @param ticker The ticker object.
AnnaBridge 156:ff21514d8981 164 * @return The current timestamp
AnnaBridge 156:ff21514d8981 165 */
AnnaBridge 156:ff21514d8981 166 timestamp_t ticker_read(const ticker_data_t *const ticker);
AnnaBridge 156:ff21514d8981 167
AnnaBridge 156:ff21514d8981 168 /** Read the current (absolute) ticker's timestamp
AnnaBridge 156:ff21514d8981 169 *
AnnaBridge 156:ff21514d8981 170 * @warning Return an absolute timestamp counting from the initialization of the
AnnaBridge 156:ff21514d8981 171 * ticker.
AnnaBridge 156:ff21514d8981 172 *
AnnaBridge 156:ff21514d8981 173 * @param ticker The ticker object.
AnnaBridge 156:ff21514d8981 174 * @return The current timestamp
AnnaBridge 156:ff21514d8981 175 */
AnnaBridge 156:ff21514d8981 176 us_timestamp_t ticker_read_us(const ticker_data_t *const ticker);
AnnaBridge 156:ff21514d8981 177
AnnaBridge 156:ff21514d8981 178 /** Read the next event's timestamp
AnnaBridge 156:ff21514d8981 179 *
AnnaBridge 156:ff21514d8981 180 * @param ticker The ticker object.
AnnaBridge 156:ff21514d8981 181 * @param timestamp The timestamp object.
AnnaBridge 156:ff21514d8981 182 * @return 1 if timestamp is pending event, 0 if there's no event pending
AnnaBridge 156:ff21514d8981 183 */
AnnaBridge 156:ff21514d8981 184 int ticker_get_next_timestamp(const ticker_data_t *const ticker, timestamp_t *timestamp);
AnnaBridge 156:ff21514d8981 185
Anna Bridge 160:5571c4ff569f 186 /* Private functions
Anna Bridge 160:5571c4ff569f 187 *
Anna Bridge 160:5571c4ff569f 188 * @cond PRIVATE
Anna Bridge 160:5571c4ff569f 189 *
Anna Bridge 160:5571c4ff569f 190 */
Anna Bridge 160:5571c4ff569f 191
Anna Bridge 160:5571c4ff569f 192 int _ticker_match_interval_passed(timestamp_t prev_tick, timestamp_t cur_tick, timestamp_t match_tick);
Anna Bridge 160:5571c4ff569f 193
Anna Bridge 160:5571c4ff569f 194 /*
Anna Bridge 160:5571c4ff569f 195 * @endcond PRIVATE
Anna Bridge 160:5571c4ff569f 196 *
Anna Bridge 160:5571c4ff569f 197 */
Anna Bridge 160:5571c4ff569f 198
AnnaBridge 156:ff21514d8981 199 /**@}*/
AnnaBridge 156:ff21514d8981 200
AnnaBridge 156:ff21514d8981 201 #ifdef __cplusplus
AnnaBridge 156:ff21514d8981 202 }
AnnaBridge 156:ff21514d8981 203 #endif
AnnaBridge 156:ff21514d8981 204
AnnaBridge 156:ff21514d8981 205 #endif
AnnaBridge 156:ff21514d8981 206
AnnaBridge 156:ff21514d8981 207 /** @}*/