CTU_FEL_B3B38LPE_2018 / Mbed 2 deprecated mbed_button

NUCLEO-F042K6 Simple demo with buttons intterupt changing PWM DC - with autoincrement when button pressed longer than 1s

Dependencies:   mbed

main.cpp@3:5edb1ea41029, 2018-02-17 (annotated)

Committer:
vodsejak
Date:
Sat Feb 17 17:26:47 2018 +0000
Revision:
3:5edb1ea41029
Parent:
2:b5b8bda0bcda 
v 3.0; added internal pull ups;

Who changed what in which revision?

UserRevisionLine numberNew contents of line
vodsejak 1:127786980842 1 #include "mbed.h" // import of mbed library (required)
vodsejak 1:127786980842 2 /*******************************************************************************
vodsejak 1:127786980842 3
vodsejak 1:127786980842 4 EXAMPLE DESCRIPTION
vodsejak 1:127786980842 5
vodsejak 3:5edb1ea41029 6 Uses two buttons connected to PA_0 - plus and PA_1 - minus with internal pull
vodsejak 3:5edb1ea41029 7 up resistors. On PA_8 is PWM output with variable duty cycle (DC) and frequncy
vodsejak 3:5edb1ea41029 8 of 500 Hz.DC can be changed true buttons. On press of button DC is incremented
vodsejak 1:127786980842 9 or decremented by 0.01. Interrupt is attached to falling edge on appropriate
vodsejak 1:127786980842 10 pin and process of incrementation/decrementation is driven throu this
vodsejak 1:127786980842 11 interrupt. Programm also demonstrates auto incrementation/decrementation while
vodsejak 1:127786980842 12 button is pressed for longer than 1 s. After button is pressed timer is
vodsejak 1:127786980842 13 started. Ticker periodically (every 10 ms) calls function that checks timer
vodsejak 1:127786980842 14 value. If the timer had counted more than 1 s, It is stopped and auto
vodsejak 1:127786980842 15 incementation/decrementation is stared (+-0.01 every 500 ms). After button
vodsejak 1:127786980842 16 release auto incementation/decrementation is stopped and timer reset.
vodsejak 1:127786980842 17 Programm is written in way, that there can NOT be simultaneously active both
vodsejak 1:127786980842 18 auto incrementation and decrementation. Note that there are also prints to
vodsejak 1:127786980842 19 UART to check states of buttons and change of DC.
vodsejak 1:127786980842 20
vodsejak 1:127786980842 21 *******************************************************************************/
vodsejak 0:602adf33625c 22
vodsejak 3:5edb1ea41029 23 InterruptIn buttonPlus(PA_0); // deffition of interrupt
vodsejak 0:602adf33625c 24 InterruptIn buttonMinus(PA_1); // deffition of interrupt
vodsejak 0:602adf33625c 25
vodsejak 0:602adf33625c 26 PwmOut PWM(PA_8); // definition of PWM pin
vodsejak 0:602adf33625c 27
vodsejak 0:602adf33625c 28 Timer tim; // Timer definition
vodsejak 0:602adf33625c 29
vodsejak 1:127786980842 30 Ticker tick; // Ticker definition
vodsejak 1:127786980842 31
vodsejak 1:127786980842 32 bool autoIncrement=false; // true - do autoincrement
vodsejak 1:127786980842 33 // false - do not autoincrement
vodsejak 0:602adf33625c 34
vodsejak 1:127786980842 35 bool plus=true; // true - auto increment
vodsejak 1:127786980842 36 // false - auto decrement
vodsejak 0:602adf33625c 37
vodsejak 1:127786980842 38 // called after falling edge on PA_0
vodsejak 1:127786980842 39 // starts timer for auto increment check
vodsejak 1:127786980842 40 // increments DC
vodsejak 0:602adf33625c 41 void pressedPlus() {
vodsejak 0:602adf33625c 42 tim.start(); // start Timer
vodsejak 1:127786980842 43 plus=true; // incrementation
vodsejak 0:602adf33625c 44 if (PWM.read()+0.01 <= 1) {
vodsejak 1:127786980842 45 PWM.write(PWM.read()+0.01);
vodsejak 3:5edb1ea41029 46 printf("Presed plus button. DC: %f.\n",PWM.read());
vodsejak 0:602adf33625c 47 }else{
vodsejak 0:602adf33625c 48 PWM.write(1);
vodsejak 3:5edb1ea41029 49 printf("Presed plus button. Already maximum DC.\n");
vodsejak 0:602adf33625c 50 }
vodsejak 0:602adf33625c 51 }
vodsejak 0:602adf33625c 52
vodsejak 1:127786980842 53 // called after rising edge on PA_0
vodsejak 1:127786980842 54 // stops and resets auto increment timer
vodsejak 1:127786980842 55 // stops auto increment
vodsejak 0:602adf33625c 56 void releasedPlus(){
vodsejak 0:602adf33625c 57 tim.stop();
vodsejak 0:602adf33625c 58 tim.reset();
vodsejak 0:602adf33625c 59 autoIncrement=false;
vodsejak 3:5edb1ea41029 60 printf("Plus button released.\n");
vodsejak 0:602adf33625c 61 }
vodsejak 0:602adf33625c 62
vodsejak 1:127786980842 63 // called after falling edge on PA_1
vodsejak 1:127786980842 64 // starts timer for auto decrement check
vodsejak 1:127786980842 65 // decrements DC
vodsejak 0:602adf33625c 66 void pressedMinus() {
vodsejak 0:602adf33625c 67 tim.start(); // start Timer
vodsejak 1:127786980842 68 plus=false; // decrementation
vodsejak 0:602adf33625c 69 if (PWM.read()-0.01 >= 0) {
vodsejak 0:602adf33625c 70 PWM.write(PWM.read()-0.01);
vodsejak 3:5edb1ea41029 71 printf("Presed minus button. DC: %f\n",PWM.read());
vodsejak 0:602adf33625c 72 }else{
vodsejak 0:602adf33625c 73 PWM.write(0);
vodsejak 3:5edb1ea41029 74 printf("Presed minus button. Already minimum DC.\n");
vodsejak 0:602adf33625c 75 }
vodsejak 0:602adf33625c 76 }
vodsejak 0:602adf33625c 77
vodsejak 1:127786980842 78 // called after rising edge on PA_1
vodsejak 1:127786980842 79 // stops and resets auto decrement timer
vodsejak 1:127786980842 80 // stops auto decrement
vodsejak 0:602adf33625c 81 void releasedMinus(){
vodsejak 0:602adf33625c 82 tim.stop();
vodsejak 0:602adf33625c 83 tim.reset();
vodsejak 0:602adf33625c 84 autoIncrement=false;
vodsejak 3:5edb1ea41029 85 printf("Minus button released.\n");
vodsejak 0:602adf33625c 86 }
vodsejak 0:602adf33625c 87
vodsejak 1:127786980842 88
vodsejak 1:127786980842 89 // checks timer value
vodsejak 1:127786980842 90 // if > 1 s starts auto incerement/decrement
vodsejak 0:602adf33625c 91 void checkTimer(){
vodsejak 0:602adf33625c 92 if(tim.read_ms()>1000){
vodsejak 0:602adf33625c 93 tim.stop();
vodsejak 0:602adf33625c 94 autoIncrement=true;
vodsejak 0:602adf33625c 95 }
vodsejak 0:602adf33625c 96 }
vodsejak 0:602adf33625c 97
vodsejak 0:602adf33625c 98 int main()
vodsejak 0:602adf33625c 99 {
vodsejak 0:602adf33625c 100
vodsejak 0:602adf33625c 101 // Set PWM
vodsejak 0:602adf33625c 102 PWM.period_ms(2); // 500 Hz
vodsejak 0:602adf33625c 103 PWM.write(0); // duration of active pulse
vodsejak 0:602adf33625c 104
vodsejak 1:127786980842 105 // Set buttons interrupts
vodsejak 0:602adf33625c 106 buttonPlus.fall(&pressedPlus);
vodsejak 0:602adf33625c 107 buttonMinus.fall(&pressedMinus);
vodsejak 0:602adf33625c 108 buttonPlus.rise(&releasedPlus);
vodsejak 0:602adf33625c 109 buttonMinus.rise(&releasedMinus);
vodsejak 0:602adf33625c 110
vodsejak 3:5edb1ea41029 111 // internal pull ups
vodsejak 3:5edb1ea41029 112 buttonPlus.mode(PullUp);
vodsejak 3:5edb1ea41029 113 buttonMinus.mode(PullUp);
vodsejak 3:5edb1ea41029 114
vodsejak 1:127786980842 115 // set ticker interrupt
vodsejak 0:602adf33625c 116 tick.attach(&checkTimer,0.01);
vodsejak 0:602adf33625c 117
vodsejak 0:602adf33625c 118 while (1) {
vodsejak 1:127786980842 119 // check if auto increment/decrement
vodsejak 0:602adf33625c 120 if(autoIncrement && plus && PWM.read()+0.01 <= 1){
vodsejak 0:602adf33625c 121 PWM.write(PWM.read()+0.01);
vodsejak 3:5edb1ea41029 122 printf("Autoincrement. DC: %f.\n",PWM.read());
vodsejak 0:602adf33625c 123 }
vodsejak 0:602adf33625c 124 else if(autoIncrement && !plus && PWM.read()-0.01 >= 0){
vodsejak 0:602adf33625c 125 PWM.write(PWM.read()-0.01);
vodsejak 3:5edb1ea41029 126 printf("Autodecrement. DC: %f.\n",PWM.read());
vodsejak 0:602adf33625c 127 }
vodsejak 0:602adf33625c 128 wait_ms(500);
vodsejak 0:602adf33625c 129 }
vodsejak 0:602adf33625c 130 }