Ultra-sensitive magnetometer / aurora sensor

1/*
2 * Grove Magenetometer sensor v1.0
3 * August 2022
4*/ 
5
6#include <Wire.h>
7#include "rgb_lcd.h"
8
9rgb_lcd lcd;
10
11const int colorR = 255;
12const int colorG = 0;
13const int colorB = 0;
14
15/* Define names for used pins */
16int sensorDig = 3;                        // D2 connector (D3 input for digital)
17
18/* Define sensor update rate in ms */
19unsigned int updateRate = 500;
20
21/* Define sensor measure time in ms */
22unsigned int measureTime = 100;
23
24/* Define variables */
25int state = 0;                            //Stores current state
26volatile unsigned int intEnable = 0;      //0-counter for sensors is not incremented; 1-counter for sensors is incremented
27volatile unsigned long sensorDigCnt = 0;  //Stores number of counted changes for Digital sensor
28volatile int sensorAnalog = 0;            //Variable to store the value coming from the analog sensor
29unsigned long prevMillis = 0;             //Stores previous millis() for calculating refresh rate
30
31
32/* Setup loop */
33void setup() {
34  /* Setup LCD column and row number */
35  lcd.begin(16, 2);
36  lcd.setRGB(colorR, colorG, colorB);
37
38  lcd.setCursor(0,0);
39  lcd.print("GROVE MAG SENSOR");
40
41  /* Setup pins */
42  pinMode(sensorDig, INPUT);
43
44  /* Setup interrupts */
45  attachInterrupt(digitalPinToInterrupt(sensorDig), sensorDigHandler, RISING); 
46}
47
48/* Main loop */
49void loop() {
50  /* Measure current time */
51  unsigned long currMillis = millis();
52
53  /* State machine - user can add more states */
54  switch(state){
55    /* Calculate new sensor data and update LCD */
56    case 1:     
57      /* Calculate number of actual pulses per [ms]
58         Divide by 2 since we measure change in signal and by measureTime to get number of pulses per [ms]*/
59         
60      sensorDigCnt = (sensorDigCnt);
61
62      /* Update LCD */
63      lcdUpdate(sensorDigCnt);
64      
65      /* Reset variables */
66      state = 0;
67      
68    /* User can add more cases (states) here */
69  }
70
71  /* If defined sensor update rate has passed measure sensors */
72  if(currMillis - prevMillis >= updateRate) {
73    /* Reset variables */
74    sensorDigCnt = 0;
75     
76    /* Save current time */
77    prevMillis = currMillis;
78
79    /* Measure number of changes in signal for defined time */
80    intEnable = 1;
81    delay(measureTime); 
82    intEnable = 0;
83    
84    /* Enable state 1 */
85    state = 1;
86  }
87  
88}
89
90/* Digital sensor interrupt handler */
91void sensorDigHandler(){
92  if (intEnable==1)
93    sensorDigCnt++;
94}
95
96/* Function to update the LCD */
97void lcdUpdate(unsigned long sensorD){
98  /*Write new data to LCD */
99    lcd.setCursor(0,1);
100    lcd.print("     ");
101    if(sensorD>9999){
102      lcd.print(sensorD);
103    }
104    else{
105       lcd.print(" ");
106       lcd.print(sensorD);
107    }
108}