Neil Johnson / microbit-ARMBand

Official Sheffield ARMBand micro:bit program

microbit/microbit-dal/source/drivers/MicroBitButton.cpp@0:b9164b348919, 2016-10-17 (annotated)

Committer:
MrBedfordVan
Date:
Mon Oct 17 12:41:20 2016 +0000
Revision:
0:b9164b348919
Official Sheffield ARMBand Micro:bit program

Who changed what in which revision?

UserRevisionLine numberNew contents of line
MrBedfordVan 0:b9164b348919 1 /*
MrBedfordVan 0:b9164b348919 2 The MIT License (MIT)
MrBedfordVan 0:b9164b348919 3
MrBedfordVan 0:b9164b348919 4 Copyright (c) 2016 British Broadcasting Corporation.
MrBedfordVan 0:b9164b348919 5 This software is provided by Lancaster University by arrangement with the BBC.
MrBedfordVan 0:b9164b348919 6
MrBedfordVan 0:b9164b348919 7 Permission is hereby granted, free of charge, to any person obtaining a
MrBedfordVan 0:b9164b348919 8 copy of this software and associated documentation files (the "Software"),
MrBedfordVan 0:b9164b348919 9 to deal in the Software without restriction, including without limitation
MrBedfordVan 0:b9164b348919 10 the rights to use, copy, modify, merge, publish, distribute, sublicense,
MrBedfordVan 0:b9164b348919 11 and/or sell copies of the Software, and to permit persons to whom the
MrBedfordVan 0:b9164b348919 12 Software is furnished to do so, subject to the following conditions:
MrBedfordVan 0:b9164b348919 13
MrBedfordVan 0:b9164b348919 14 The above copyright notice and this permission notice shall be included in
MrBedfordVan 0:b9164b348919 15 all copies or substantial portions of the Software.
MrBedfordVan 0:b9164b348919 16
MrBedfordVan 0:b9164b348919 17 THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
MrBedfordVan 0:b9164b348919 18 IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
MrBedfordVan 0:b9164b348919 19 FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
MrBedfordVan 0:b9164b348919 20 THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
MrBedfordVan 0:b9164b348919 21 LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
MrBedfordVan 0:b9164b348919 22 FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER
MrBedfordVan 0:b9164b348919 23 DEALINGS IN THE SOFTWARE.
MrBedfordVan 0:b9164b348919 24 */
MrBedfordVan 0:b9164b348919 25
MrBedfordVan 0:b9164b348919 26 #include "MicroBitConfig.h"
MrBedfordVan 0:b9164b348919 27 #include "MicroBitButton.h"
MrBedfordVan 0:b9164b348919 28 #include "MicroBitSystemTimer.h"
MrBedfordVan 0:b9164b348919 29
MrBedfordVan 0:b9164b348919 30 /**
MrBedfordVan 0:b9164b348919 31 * Constructor.
MrBedfordVan 0:b9164b348919 32 *
MrBedfordVan 0:b9164b348919 33 * Create a software representation of a button.
MrBedfordVan 0:b9164b348919 34 *
MrBedfordVan 0:b9164b348919 35 * @param name the physical pin on the processor that should be used as input.
MrBedfordVan 0:b9164b348919 36 *
MrBedfordVan 0:b9164b348919 37 * @param id the ID of the new MicroBitButton object.
MrBedfordVan 0:b9164b348919 38 *
MrBedfordVan 0:b9164b348919 39 * @param eventConfiguration Configures the events that will be generated by this MicroBitButton instance.
MrBedfordVan 0:b9164b348919 40 * Defaults to MICROBIT_BUTTON_ALL_EVENTS.
MrBedfordVan 0:b9164b348919 41 *
MrBedfordVan 0:b9164b348919 42 * @param mode the configuration of internal pullups/pulldowns, as defined in the mbed PinMode class. PullNone by default.
MrBedfordVan 0:b9164b348919 43 *
MrBedfordVan 0:b9164b348919 44 * @code
MrBedfordVan 0:b9164b348919 45 * buttonA(MICROBIT_PIN_BUTTON_A, MICROBIT_ID_BUTTON_A);
MrBedfordVan 0:b9164b348919 46 * @endcode
MrBedfordVan 0:b9164b348919 47 */
MrBedfordVan 0:b9164b348919 48 MicroBitButton::MicroBitButton(PinName name, uint16_t id, MicroBitButtonEventConfiguration eventConfiguration, PinMode mode) : pin(name, mode)
MrBedfordVan 0:b9164b348919 49 {
MrBedfordVan 0:b9164b348919 50 this->id = id;
MrBedfordVan 0:b9164b348919 51 this->name = name;
MrBedfordVan 0:b9164b348919 52 this->eventConfiguration = eventConfiguration;
MrBedfordVan 0:b9164b348919 53 this->downStartTime = 0;
MrBedfordVan 0:b9164b348919 54 this->sigma = 0;
MrBedfordVan 0:b9164b348919 55 system_timer_add_component(this);
MrBedfordVan 0:b9164b348919 56 }
MrBedfordVan 0:b9164b348919 57
MrBedfordVan 0:b9164b348919 58 /**
MrBedfordVan 0:b9164b348919 59 * Changes the event configuration used by this button to the given MicroBitButtonEventConfiguration.
MrBedfordVan 0:b9164b348919 60 *
MrBedfordVan 0:b9164b348919 61 * All subsequent events generated by this button will then be informed by this configuraiton.
MrBedfordVan 0:b9164b348919 62 *
MrBedfordVan 0:b9164b348919 63 * @param config The new configuration for this button. Legal values are MICROBIT_BUTTON_ALL_EVENTS or MICROBIT_BUTTON_SIMPLE_EVENTS.
MrBedfordVan 0:b9164b348919 64 *
MrBedfordVan 0:b9164b348919 65 * Example:
MrBedfordVan 0:b9164b348919 66 * @code
MrBedfordVan 0:b9164b348919 67 * // Configure a button to generate all possible events.
MrBedfordVan 0:b9164b348919 68 * buttonA.setEventConfiguration(MICROBIT_BUTTON_ALL_EVENTS);
MrBedfordVan 0:b9164b348919 69 *
MrBedfordVan 0:b9164b348919 70 * // Configure a button to suppress MICROBIT_BUTTON_EVT_CLICK and MICROBIT_BUTTON_EVT_LONG_CLICK events.
MrBedfordVan 0:b9164b348919 71 * buttonA.setEventConfiguration(MICROBIT_BUTTON_SIMPLE_EVENTS);
MrBedfordVan 0:b9164b348919 72 * @endcode
MrBedfordVan 0:b9164b348919 73 */
MrBedfordVan 0:b9164b348919 74 void MicroBitButton::setEventConfiguration(MicroBitButtonEventConfiguration config)
MrBedfordVan 0:b9164b348919 75 {
MrBedfordVan 0:b9164b348919 76 this->eventConfiguration = config;
MrBedfordVan 0:b9164b348919 77 }
MrBedfordVan 0:b9164b348919 78
MrBedfordVan 0:b9164b348919 79 /**
MrBedfordVan 0:b9164b348919 80 * periodic callback from MicroBit system timer.
MrBedfordVan 0:b9164b348919 81 *
MrBedfordVan 0:b9164b348919 82 * Check for state change for this button, and fires various events on a state change.
MrBedfordVan 0:b9164b348919 83 */
MrBedfordVan 0:b9164b348919 84 void MicroBitButton::systemTick()
MrBedfordVan 0:b9164b348919 85 {
MrBedfordVan 0:b9164b348919 86 //
MrBedfordVan 0:b9164b348919 87 // If the pin is pulled low (touched), increment our culumative counter.
MrBedfordVan 0:b9164b348919 88 // otherwise, decrement it. We're essentially building a lazy follower here.
MrBedfordVan 0:b9164b348919 89 // This makes the output debounced for buttons, and desensitizes touch sensors
MrBedfordVan 0:b9164b348919 90 // (particularly in environments where there is mains noise!)
MrBedfordVan 0:b9164b348919 91 //
MrBedfordVan 0:b9164b348919 92 if(!pin)
MrBedfordVan 0:b9164b348919 93 {
MrBedfordVan 0:b9164b348919 94 if (sigma < MICROBIT_BUTTON_SIGMA_MAX)
MrBedfordVan 0:b9164b348919 95 sigma++;
MrBedfordVan 0:b9164b348919 96 }
MrBedfordVan 0:b9164b348919 97 else
MrBedfordVan 0:b9164b348919 98 {
MrBedfordVan 0:b9164b348919 99 if (sigma > MICROBIT_BUTTON_SIGMA_MIN)
MrBedfordVan 0:b9164b348919 100 sigma--;
MrBedfordVan 0:b9164b348919 101 }
MrBedfordVan 0:b9164b348919 102
MrBedfordVan 0:b9164b348919 103 // Check to see if we have off->on state change.
MrBedfordVan 0:b9164b348919 104 if(sigma > MICROBIT_BUTTON_SIGMA_THRESH_HI && !(status & MICROBIT_BUTTON_STATE))
MrBedfordVan 0:b9164b348919 105 {
MrBedfordVan 0:b9164b348919 106 // Record we have a state change, and raise an event.
MrBedfordVan 0:b9164b348919 107 status |= MICROBIT_BUTTON_STATE;
MrBedfordVan 0:b9164b348919 108 MicroBitEvent evt(id,MICROBIT_BUTTON_EVT_DOWN);
MrBedfordVan 0:b9164b348919 109
MrBedfordVan 0:b9164b348919 110 //Record the time the button was pressed.
MrBedfordVan 0:b9164b348919 111 downStartTime = system_timer_current_time();
MrBedfordVan 0:b9164b348919 112 }
MrBedfordVan 0:b9164b348919 113
MrBedfordVan 0:b9164b348919 114 // Check to see if we have on->off state change.
MrBedfordVan 0:b9164b348919 115 if(sigma < MICROBIT_BUTTON_SIGMA_THRESH_LO && (status & MICROBIT_BUTTON_STATE))
MrBedfordVan 0:b9164b348919 116 {
MrBedfordVan 0:b9164b348919 117 status = 0;
MrBedfordVan 0:b9164b348919 118 MicroBitEvent evt(id,MICROBIT_BUTTON_EVT_UP);
MrBedfordVan 0:b9164b348919 119
MrBedfordVan 0:b9164b348919 120 if (eventConfiguration == MICROBIT_BUTTON_ALL_EVENTS)
MrBedfordVan 0:b9164b348919 121 {
MrBedfordVan 0:b9164b348919 122 //determine if this is a long click or a normal click and send event
MrBedfordVan 0:b9164b348919 123 if((system_timer_current_time() - downStartTime) >= MICROBIT_BUTTON_LONG_CLICK_TIME)
MrBedfordVan 0:b9164b348919 124 MicroBitEvent evt(id,MICROBIT_BUTTON_EVT_LONG_CLICK);
MrBedfordVan 0:b9164b348919 125 else
MrBedfordVan 0:b9164b348919 126 MicroBitEvent evt(id,MICROBIT_BUTTON_EVT_CLICK);
MrBedfordVan 0:b9164b348919 127 }
MrBedfordVan 0:b9164b348919 128 }
MrBedfordVan 0:b9164b348919 129
MrBedfordVan 0:b9164b348919 130 //if button is pressed and the hold triggered event state is not triggered AND we are greater than the button debounce value
MrBedfordVan 0:b9164b348919 131 if((status & MICROBIT_BUTTON_STATE) && !(status & MICROBIT_BUTTON_STATE_HOLD_TRIGGERED) && (system_timer_current_time() - downStartTime) >= MICROBIT_BUTTON_HOLD_TIME)
MrBedfordVan 0:b9164b348919 132 {
MrBedfordVan 0:b9164b348919 133 //set the hold triggered event flag
MrBedfordVan 0:b9164b348919 134 status |= MICROBIT_BUTTON_STATE_HOLD_TRIGGERED;
MrBedfordVan 0:b9164b348919 135
MrBedfordVan 0:b9164b348919 136 //fire hold event
MrBedfordVan 0:b9164b348919 137 MicroBitEvent evt(id,MICROBIT_BUTTON_EVT_HOLD);
MrBedfordVan 0:b9164b348919 138 }
MrBedfordVan 0:b9164b348919 139 }
MrBedfordVan 0:b9164b348919 140
MrBedfordVan 0:b9164b348919 141 /**
MrBedfordVan 0:b9164b348919 142 * Tests if this Button is currently pressed.
MrBedfordVan 0:b9164b348919 143 *
MrBedfordVan 0:b9164b348919 144 * @code
MrBedfordVan 0:b9164b348919 145 * if(buttonA.isPressed())
MrBedfordVan 0:b9164b348919 146 * display.scroll("Pressed!");
MrBedfordVan 0:b9164b348919 147 * @endcode
MrBedfordVan 0:b9164b348919 148 *
MrBedfordVan 0:b9164b348919 149 * @return 1 if this button is pressed, 0 otherwise.
MrBedfordVan 0:b9164b348919 150 */
MrBedfordVan 0:b9164b348919 151 int MicroBitButton::isPressed()
MrBedfordVan 0:b9164b348919 152 {
MrBedfordVan 0:b9164b348919 153 return status & MICROBIT_BUTTON_STATE ? 1 : 0;
MrBedfordVan 0:b9164b348919 154 }
MrBedfordVan 0:b9164b348919 155
MrBedfordVan 0:b9164b348919 156 /**
MrBedfordVan 0:b9164b348919 157 * Destructor for MicroBitButton, where we deregister this instance from the array of fiber components.
MrBedfordVan 0:b9164b348919 158 */
MrBedfordVan 0:b9164b348919 159 MicroBitButton::~MicroBitButton()
MrBedfordVan 0:b9164b348919 160 {
MrBedfordVan 0:b9164b348919 161 system_timer_remove_component(this);
MrBedfordVan 0:b9164b348919 162 }