Wendy Warne / microbit-dal

updates

Dependencies:   BLE_API mbed-dev-bin nRF51822

Fork of microbit-dal-eddystone by Martin Woolley

source/core/MicroBitSystemTimer.cpp@29:62f8b007debf, 2016-07-13 (annotated)

Committer:
LancasterUniversity
Date:
Wed Jul 13 12:18:07 2016 +0100
Revision:
29:62f8b007debf
Parent:
1:8aa5cdb4ab67
Child:
31:87789e55bac7
Synchronized with git rev 0048a9ac

Author: James Devine

microbit-dal: fixed UART service buffer sizing, and re-enabled config options for default services



There was a perspective mismatch with the UART service, where the

actual buffer size given in the constructor, did not reflect the size

of the user buffer that was available to the application. This was not

documented, and hence cause confusion. The patch applied in this

commit, increments the given buffer sizes by one, so that the

application buffer has the available size given in the constructor.



Additionally, some configuration options were lost during the component

refactor, these have now been restored.

Who changed what in which revision?

UserRevisionLine numberNew contents of line
Jonathan Austin 1:8aa5cdb4ab67 1 /*
Jonathan Austin 1:8aa5cdb4ab67 2 The MIT License (MIT)
Jonathan Austin 1:8aa5cdb4ab67 3
Jonathan Austin 1:8aa5cdb4ab67 4 Copyright (c) 2016 British Broadcasting Corporation.
Jonathan Austin 1:8aa5cdb4ab67 5 This software is provided by Lancaster University by arrangement with the BBC.
Jonathan Austin 1:8aa5cdb4ab67 6
Jonathan Austin 1:8aa5cdb4ab67 7 Permission is hereby granted, free of charge, to any person obtaining a
Jonathan Austin 1:8aa5cdb4ab67 8 copy of this software and associated documentation files (the "Software"),
Jonathan Austin 1:8aa5cdb4ab67 9 to deal in the Software without restriction, including without limitation
Jonathan Austin 1:8aa5cdb4ab67 10 the rights to use, copy, modify, merge, publish, distribute, sublicense,
Jonathan Austin 1:8aa5cdb4ab67 11 and/or sell copies of the Software, and to permit persons to whom the
Jonathan Austin 1:8aa5cdb4ab67 12 Software is furnished to do so, subject to the following conditions:
Jonathan Austin 1:8aa5cdb4ab67 13
Jonathan Austin 1:8aa5cdb4ab67 14 The above copyright notice and this permission notice shall be included in
Jonathan Austin 1:8aa5cdb4ab67 15 all copies or substantial portions of the Software.
Jonathan Austin 1:8aa5cdb4ab67 16
Jonathan Austin 1:8aa5cdb4ab67 17 THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
Jonathan Austin 1:8aa5cdb4ab67 18 IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
Jonathan Austin 1:8aa5cdb4ab67 19 FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
Jonathan Austin 1:8aa5cdb4ab67 20 THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
Jonathan Austin 1:8aa5cdb4ab67 21 LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
Jonathan Austin 1:8aa5cdb4ab67 22 FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER
Jonathan Austin 1:8aa5cdb4ab67 23 DEALINGS IN THE SOFTWARE.
Jonathan Austin 1:8aa5cdb4ab67 24 */
Jonathan Austin 1:8aa5cdb4ab67 25
Jonathan Austin 1:8aa5cdb4ab67 26 /**
Jonathan Austin 1:8aa5cdb4ab67 27 * Definitions for the MicroBit system timer.
Jonathan Austin 1:8aa5cdb4ab67 28 *
Jonathan Austin 1:8aa5cdb4ab67 29 * This module provides:
Jonathan Austin 1:8aa5cdb4ab67 30 *
Jonathan Austin 1:8aa5cdb4ab67 31 * 1) a concept of global system time since power up
Jonathan Austin 1:8aa5cdb4ab67 32 * 2) a simple periodic multiplexing API for the underlying mbed implementation.
Jonathan Austin 1:8aa5cdb4ab67 33 *
Jonathan Austin 1:8aa5cdb4ab67 34 * The latter is useful to avoid costs associated with multiple mbed Ticker instances
Jonathan Austin 1:8aa5cdb4ab67 35 * in microbit-dal components, as each incurs a significant additional RAM overhead (circa 80 bytes).
Jonathan Austin 1:8aa5cdb4ab67 36 */
Jonathan Austin 1:8aa5cdb4ab67 37 #include "MicroBitConfig.h"
Jonathan Austin 1:8aa5cdb4ab67 38 #include "MicroBitSystemTimer.h"
Jonathan Austin 1:8aa5cdb4ab67 39 #include "ErrorNo.h"
Jonathan Austin 1:8aa5cdb4ab67 40
Jonathan Austin 1:8aa5cdb4ab67 41 /*
Jonathan Austin 1:8aa5cdb4ab67 42 * Time since power on. Measured in milliseconds.
Jonathan Austin 1:8aa5cdb4ab67 43 * When stored as an unsigned long, this gives us approx 50 days between rollover, which is ample. :-)
Jonathan Austin 1:8aa5cdb4ab67 44 */
Jonathan Austin 1:8aa5cdb4ab67 45 static unsigned long ticks = 0;
Jonathan Austin 1:8aa5cdb4ab67 46 static unsigned int tick_period = 0;
Jonathan Austin 1:8aa5cdb4ab67 47
Jonathan Austin 1:8aa5cdb4ab67 48 // Array of components which are iterated during a system tick
Jonathan Austin 1:8aa5cdb4ab67 49 static MicroBitComponent* systemTickComponents[MICROBIT_SYSTEM_COMPONENTS];
Jonathan Austin 1:8aa5cdb4ab67 50
Jonathan Austin 1:8aa5cdb4ab67 51 // Periodic callback interrupt
Jonathan Austin 1:8aa5cdb4ab67 52 static Ticker *timer = NULL;
Jonathan Austin 1:8aa5cdb4ab67 53
Jonathan Austin 1:8aa5cdb4ab67 54
Jonathan Austin 1:8aa5cdb4ab67 55 /**
Jonathan Austin 1:8aa5cdb4ab67 56 * Initialises the system wide timer.
Jonathan Austin 1:8aa5cdb4ab67 57 *
Jonathan Austin 1:8aa5cdb4ab67 58 * This must be called before any components register to receive periodic periodic callbacks.
Jonathan Austin 1:8aa5cdb4ab67 59 *
Jonathan Austin 1:8aa5cdb4ab67 60 * @param timer_period The initial period between interrupts, in millseconds.
Jonathan Austin 1:8aa5cdb4ab67 61 *
Jonathan Austin 1:8aa5cdb4ab67 62 * @return MICROBIT_OK on success.
Jonathan Austin 1:8aa5cdb4ab67 63 */
Jonathan Austin 1:8aa5cdb4ab67 64 int system_timer_init(int period)
Jonathan Austin 1:8aa5cdb4ab67 65 {
Jonathan Austin 1:8aa5cdb4ab67 66 if (timer == NULL)
Jonathan Austin 1:8aa5cdb4ab67 67 timer = new Ticker();
Jonathan Austin 1:8aa5cdb4ab67 68
Jonathan Austin 1:8aa5cdb4ab67 69 return system_timer_set_period(period);
Jonathan Austin 1:8aa5cdb4ab67 70 }
Jonathan Austin 1:8aa5cdb4ab67 71
Jonathan Austin 1:8aa5cdb4ab67 72 /**
Jonathan Austin 1:8aa5cdb4ab67 73 * Reconfigures the system wide timer to the given period in milliseconds.
Jonathan Austin 1:8aa5cdb4ab67 74 *
Jonathan Austin 1:8aa5cdb4ab67 75 * @param period the new period of the timer in milliseconds
Jonathan Austin 1:8aa5cdb4ab67 76 *
Jonathan Austin 1:8aa5cdb4ab67 77 * @return MICROBIT_OK on success. MICROBIT_INVALID_PARAMETER is returned if period < 1
Jonathan Austin 1:8aa5cdb4ab67 78 */
Jonathan Austin 1:8aa5cdb4ab67 79 int system_timer_set_period(int period)
Jonathan Austin 1:8aa5cdb4ab67 80 {
Jonathan Austin 1:8aa5cdb4ab67 81 if (period < 1)
Jonathan Austin 1:8aa5cdb4ab67 82 return MICROBIT_INVALID_PARAMETER;
Jonathan Austin 1:8aa5cdb4ab67 83
Jonathan Austin 1:8aa5cdb4ab67 84 // If a timer is already running, ensure it is disabled before reconfiguring.
Jonathan Austin 1:8aa5cdb4ab67 85 if (tick_period)
Jonathan Austin 1:8aa5cdb4ab67 86 timer->detach();
Jonathan Austin 1:8aa5cdb4ab67 87
Jonathan Austin 1:8aa5cdb4ab67 88 // register a period callback to drive the scheduler and any other registered components.
Jonathan Austin 1:8aa5cdb4ab67 89 tick_period = period;
Jonathan Austin 1:8aa5cdb4ab67 90 timer->attach_us(system_timer_tick, period * 1000);
Jonathan Austin 1:8aa5cdb4ab67 91
Jonathan Austin 1:8aa5cdb4ab67 92 return MICROBIT_OK;
Jonathan Austin 1:8aa5cdb4ab67 93 }
Jonathan Austin 1:8aa5cdb4ab67 94
Jonathan Austin 1:8aa5cdb4ab67 95 /**
Jonathan Austin 1:8aa5cdb4ab67 96 * Accessor to obtain the current tick period in milliseconds
Jonathan Austin 1:8aa5cdb4ab67 97 *
Jonathan Austin 1:8aa5cdb4ab67 98 * @return the current tick period in milliseconds
Jonathan Austin 1:8aa5cdb4ab67 99 */
Jonathan Austin 1:8aa5cdb4ab67 100 int system_timer_get_period()
Jonathan Austin 1:8aa5cdb4ab67 101 {
Jonathan Austin 1:8aa5cdb4ab67 102 return tick_period;
Jonathan Austin 1:8aa5cdb4ab67 103 }
Jonathan Austin 1:8aa5cdb4ab67 104
Jonathan Austin 1:8aa5cdb4ab67 105 /**
Jonathan Austin 1:8aa5cdb4ab67 106 * Determines the time since the device was powered on.
Jonathan Austin 1:8aa5cdb4ab67 107 *
Jonathan Austin 1:8aa5cdb4ab67 108 * @return the current time since power on in milliseconds
Jonathan Austin 1:8aa5cdb4ab67 109 */
Jonathan Austin 1:8aa5cdb4ab67 110 unsigned long system_timer_current_time()
Jonathan Austin 1:8aa5cdb4ab67 111 {
Jonathan Austin 1:8aa5cdb4ab67 112 return ticks;
Jonathan Austin 1:8aa5cdb4ab67 113 }
Jonathan Austin 1:8aa5cdb4ab67 114
Jonathan Austin 1:8aa5cdb4ab67 115 /**
Jonathan Austin 1:8aa5cdb4ab67 116 * Timer callback. Called from interrupt context, once per period.
Jonathan Austin 1:8aa5cdb4ab67 117 *
Jonathan Austin 1:8aa5cdb4ab67 118 * Simply checks to determine if any fibers blocked on the sleep queue need to be woken up
Jonathan Austin 1:8aa5cdb4ab67 119 * and made runnable.
Jonathan Austin 1:8aa5cdb4ab67 120 */
Jonathan Austin 1:8aa5cdb4ab67 121 void system_timer_tick()
Jonathan Austin 1:8aa5cdb4ab67 122 {
Jonathan Austin 1:8aa5cdb4ab67 123 // increment our real-time counter.
Jonathan Austin 1:8aa5cdb4ab67 124 ticks += system_timer_get_period();
Jonathan Austin 1:8aa5cdb4ab67 125
Jonathan Austin 1:8aa5cdb4ab67 126 // Update any components registered for a callback
Jonathan Austin 1:8aa5cdb4ab67 127 for(int i = 0; i < MICROBIT_SYSTEM_COMPONENTS; i++)
Jonathan Austin 1:8aa5cdb4ab67 128 if(systemTickComponents[i] != NULL)
Jonathan Austin 1:8aa5cdb4ab67 129 systemTickComponents[i]->systemTick();
Jonathan Austin 1:8aa5cdb4ab67 130 }
Jonathan Austin 1:8aa5cdb4ab67 131
Jonathan Austin 1:8aa5cdb4ab67 132 /**
Jonathan Austin 1:8aa5cdb4ab67 133 * Add a component to the array of system components. This component will then receive
Jonathan Austin 1:8aa5cdb4ab67 134 * periodic callbacks, once every tick period.
Jonathan Austin 1:8aa5cdb4ab67 135 *
Jonathan Austin 1:8aa5cdb4ab67 136 * @param component The component to add.
Jonathan Austin 1:8aa5cdb4ab67 137 *
Jonathan Austin 1:8aa5cdb4ab67 138 * @return MICROBIT_OK on success. MICROBIT_NO_RESOURCES is returned if the component array is full.
Jonathan Austin 1:8aa5cdb4ab67 139 *
Jonathan Austin 1:8aa5cdb4ab67 140 * @note The callback will be in interrupt context.
Jonathan Austin 1:8aa5cdb4ab67 141 */
Jonathan Austin 1:8aa5cdb4ab67 142 int system_timer_add_component(MicroBitComponent *component)
Jonathan Austin 1:8aa5cdb4ab67 143 {
Jonathan Austin 1:8aa5cdb4ab67 144 int i = 0;
Jonathan Austin 1:8aa5cdb4ab67 145
Jonathan Austin 1:8aa5cdb4ab67 146 // If we haven't been initialized, bring up the timer with the default period.
Jonathan Austin 1:8aa5cdb4ab67 147 if (timer == NULL)
Jonathan Austin 1:8aa5cdb4ab67 148 system_timer_init(SYSTEM_TICK_PERIOD_MS);
Jonathan Austin 1:8aa5cdb4ab67 149
Jonathan Austin 1:8aa5cdb4ab67 150 while(systemTickComponents[i] != NULL && i < MICROBIT_SYSTEM_COMPONENTS)
Jonathan Austin 1:8aa5cdb4ab67 151 i++;
Jonathan Austin 1:8aa5cdb4ab67 152
Jonathan Austin 1:8aa5cdb4ab67 153 if(i == MICROBIT_SYSTEM_COMPONENTS)
Jonathan Austin 1:8aa5cdb4ab67 154 return MICROBIT_NO_RESOURCES;
Jonathan Austin 1:8aa5cdb4ab67 155
Jonathan Austin 1:8aa5cdb4ab67 156 systemTickComponents[i] = component;
Jonathan Austin 1:8aa5cdb4ab67 157 return MICROBIT_OK;
Jonathan Austin 1:8aa5cdb4ab67 158 }
Jonathan Austin 1:8aa5cdb4ab67 159
Jonathan Austin 1:8aa5cdb4ab67 160 /**
Jonathan Austin 1:8aa5cdb4ab67 161 * Remove a component from the array of system components. This component will no longer receive
Jonathan Austin 1:8aa5cdb4ab67 162 * periodic callbacks.
Jonathan Austin 1:8aa5cdb4ab67 163 *
Jonathan Austin 1:8aa5cdb4ab67 164 * @param component The component to remove.
Jonathan Austin 1:8aa5cdb4ab67 165 *
Jonathan Austin 1:8aa5cdb4ab67 166 * @return MICROBIT_OK on success. MICROBIT_INVALID_PARAMETER is returned if the given component has not been previously added.
Jonathan Austin 1:8aa5cdb4ab67 167 */
Jonathan Austin 1:8aa5cdb4ab67 168 int system_timer_remove_component(MicroBitComponent *component)
Jonathan Austin 1:8aa5cdb4ab67 169 {
Jonathan Austin 1:8aa5cdb4ab67 170 int i = 0;
Jonathan Austin 1:8aa5cdb4ab67 171
Jonathan Austin 1:8aa5cdb4ab67 172 while(systemTickComponents[i] != component && i < MICROBIT_SYSTEM_COMPONENTS)
Jonathan Austin 1:8aa5cdb4ab67 173 i++;
Jonathan Austin 1:8aa5cdb4ab67 174
Jonathan Austin 1:8aa5cdb4ab67 175 if(i == MICROBIT_SYSTEM_COMPONENTS)
Jonathan Austin 1:8aa5cdb4ab67 176 return MICROBIT_INVALID_PARAMETER;
Jonathan Austin 1:8aa5cdb4ab67 177
Jonathan Austin 1:8aa5cdb4ab67 178 systemTickComponents[i] = NULL;
Jonathan Austin 1:8aa5cdb4ab67 179
Jonathan Austin 1:8aa5cdb4ab67 180 return MICROBIT_OK;
Jonathan Austin 1:8aa5cdb4ab67 181 }