Easy adjustable minutes AC timer

1/* AC-outlet timer 1-255 minutes *
2 *  by Mans Rademaker 2021
3 *  uses Interrupt-based Rotary Encoder Sketch by Simon Merrett (see below)
4 */
5
6#include  <TM1637.h>
7int CLK = 4;
8int DIO = 5;
9TM1637 tm(CLK,DIO);
10
11long  previousMillis  = 0;        // will store last time
12long  previousMillis2= 0;        // will  store last time
13int   time2go   = 0;
14int   change    = 0;
15
16int ledState    = LOW;            // ledState used to set the LED
17long interval   = 1000;           // interval at which to blink 
18
19#define relay     12
20#define  redled    11
21
22/*******Interrupt-based Rotary Encoder Sketch*******
23by Simon  Merrett, based on insight from Oleg Mazurov, Nick Gammon, rt, Steve Spence
24*/
25static  int pinA = 2; // Our first hardware interrupt pin is digital pin 2
26static int  pinB = 3; // Our second hardware interrupt pin is digital pin 3
27volatile byte  aFlag = 0; // let's us know when we're expecting a rising edge on pinA to signal  that the encoder has arrived at a detent
28volatile byte bFlag = 0; // let's us  know when we're expecting a rising edge on pinB to signal that the encoder has arrived  at a detent (opposite direction to when aFlag is set)
29volatile byte encoderPos  = 0; //this variable stores our current value of encoder position. Change to int  or uin16_t instead of byte if you want to record a larger range than 0-255
30volatile  byte oldEncPos = 0; //stores the last encoder position value so we can compare to  the current reading and see if it has changed (so we know when to print to the serial  monitor)
31volatile byte reading = 0; //somewhere to store the direct values we  read from our interrupt pins before checking to see if we have moved a whole detent
32//*******
33
34void  setup() {
35  tm.init();
36  tm.set(2);                  //set brightness; 0-7
37  displayNumber(encoderPos);
38  pinMode(relay,    OUTPUT);
39  pinMode(redled,   OUTPUT);
40  power(LOW);
41  
42  pinMode(pinA, INPUT_PULLUP); // set pinA  as an input, pulled HIGH to the logic voltage (5V or 3.3V for most cases)
43  pinMode(pinB,  INPUT_PULLUP); // set pinB as an input, pulled HIGH to the logic voltage (5V or  3.3V for most cases)
44  attachInterrupt(0,PinA,RISING); // set an interrupt on  PinA, looking for a rising edge signal and executing the "PinA" Interrupt Service  Routine (below)
45  attachInterrupt(1,PinB,RISING); // set an interrupt on PinB,  looking for a rising edge signal and executing the "PinB" Interrupt Service Routine  (below)
46  Serial.begin(9600); // start the serial monitor link
47}
48
49void  PinA(){
50  cli(); //stop interrupts happening before we read pin values
51  reading  = PIND & 0xC; // read all eight pin values then strip away all but pinA and pinB's  values
52  if(reading == B00001100 && aFlag) { //check that we have both pins at  detent (HIGH) and that we are expecting detent on this pin's rising edge
53    encoderPos  --; //decrement the encoder's position count
54    bFlag = 0; //reset flags for  the next turn
55    aFlag = 0; //reset flags for the next turn
56  }
57  else  if (reading == B00000100) bFlag = 1; //signal that we're expecting pinB to signal  the transition to detent from free rotation
58  sei(); //restart interrupts
59}
60
61void  PinB(){
62  cli(); //stop interrupts happening before we read pin values
63  reading  = PIND & 0xC; //read all eight pin values then strip away all but pinA and pinB's  values
64  if (reading == B00001100 && bFlag) { //check that we have both pins  at detent (HIGH) and that we are expecting detent on this pin's rising edge
65    encoderPos ++; //increment the encoder's position count
66    bFlag = 0; //reset  flags for the next turn
67    aFlag = 0; //reset flags for the next turn
68  }
69  else if (reading == B00001000) aFlag = 1; //signal that we're expecting pinA to  signal the transition to detent from free rotation
70  sei(); //restart interrupts
71}
72
73void  loop(){
74unsigned long currentMillis = millis();
75
76if(currentMillis - previousMillis  > 60000) { // one minute later
77  previousMillis = currentMillis;   
78  if (time2go>0)  {time2go--;}      
79  if (time2go==0){power(LOW);}
80  displayNumber(time2go);
81}
82
83if  (time2go==1){ // last minute blink redled
84  if(currentMillis - previousMillis2  > interval) {
85    // save the last time you blinked the LED 
86    previousMillis2  = currentMillis;   
87    // if the LED is off turn it on and vice-versa:
88    if  (ledState == LOW)
89      ledState = HIGH;
90    else
91      ledState = LOW;
92    // set the LED with the ledState of the variable:
93    digitalWrite(redled,  ledState);
94  }
95}  
96  if(oldEncPos    != encoderPos) {
97    change         =  encoderPos - oldEncPos;
98    time2go        = time2go + change;
99    oldEncPos      = encoderPos;
100    displayNumber  (time2go);
101    previousMillis = currentMillis;
102    if (time2go>0){power(HIGH);} else {power(LOW);}
103  }
104}
105
106void power(int  state){
107   digitalWrite(relay,    state); 
108   digitalWrite(redled,   state);    
109}
110
111void displayNumber(int num){   
112    tm.display(3, num % 10);   
113    tm.display(2, num / 10 % 10);   
114    tm.display(1, num / 100 % 10);   
115    tm.display(0, num / 1000 % 10);
116}
117