#include <LiquidCrystal_I2C.h>
#include <Keypad.h>
LiquidCrystal_I2C lcd(0x26, 16, 3);
const byte ROWS = 4;
const byte COLS = 4;
char hexaKeys[ROWS][COLS] = {
{'1', '2', '3', 'A'},
{'4', '5', '6', 'B'},
{'7', '8', '9', 'C'},
{'*', '0', '#', 'D'}
};
byte rowPins[ROWS] = {34, 36, 38, 40};
byte colPins[COLS] = {26, 28, 30, 32};
Keypad customKeypad = Keypad(makeKeymap(hexaKeys), rowPins, colPins, ROWS, COLS);
char inputSequence[4] = " ";
int inputNumber = 0;
void setup() {
lcd.init();
lcd.clear();
lcd.backlight();
Serial.begin(115200);
lcd.print("Welcome");
}
void loop() {
char key = customKeypad.getKey();
if (key) {
Serial.print(key);
inputSequence[inputNumber] = customKeypad.getKey();
inputNumber++;
lcd.setCursor(inputNumber, 1);
lcd.print(key);
}
}
i have started on what is supposed to be an objective device for airsoft/paintball that requires you to enter a series of codes to disarm said device. i cannot for the life of me figure out how i am going to make the password portion. this device requires you to enter 4, 4 digit alphanumeric codes with numbers that will be displayed on screen in a specific sequence. you must then enter the codes in said sequence from left to right. what i just stated does not matter as i can most likely complete the rest of them with an example for storing and confirming whether just 1 code is indeed correct or incorrect.
Welcome
char inputSequence[4] = " ";
This string is 5 characters not 4, you should have a warning or an error about it
See this nice example, it may help : electronic-safe.ino - Wokwi Arduino and ESP32 Simulator
works just fine with 4. the code i showed is just the code that will display the code onto the lcd. i will go check out what you sent me.
what you sent me uses EEPROM. to my understanding there is only a finite amount of writing you can do with EEPROM. to make the boards last as long as possible i want to avoid that
The EEPROM would only be written when you wish to change the key code. I doubt you propose to do that several thousand times, let alone approach the durability of the EEPROM.
So there is no point discussing snippets, is there? 
1 Like
several hours and many fried brain cells later i finally made something thats fully functional. ill post it in a sec.
#include <Keypad.h>
#include <LiquidCrystal_I2C.h>
LiquidCrystal_I2C lcd(0x26, 16, 3);
const int ROW_NUM = 4;
const int COLUMN_NUM = 4;
char keys[ROW_NUM][COLUMN_NUM] = {
{'1', '2', '3'},
{'4', '5', '6'},
{'7', '8', '9'},
{'*', '0', '#'}
};
byte pin_rows[ROW_NUM] = {34, 36, 38, 40};
byte pin_column[COLUMN_NUM] = {26, 28, 30, 32};
Keypad customKeypad = Keypad( makeKeymap(keys), pin_rows, pin_column, ROW_NUM, COLUMN_NUM );
const String rand1 = "4478";
const String rand2 = "6940";
const String rand3 = "3312";
const String rand4 = "1675";
String ipass;
String ipass2;
String ipass3;
String ipass4;
int code_pos = 0;
char inputSequence[4] = " ";
int inputNumber = -1;
int inputNumber2 = 0;
int inputNumber3 = 0;
int inputNumber4 = 0;
void setup() {
Serial.begin(9600);
lcd.init();
lcd.clear();
lcd.backlight();
ipass.reserve(32);
ipass2.reserve(32);
ipass3.reserve(32);
ipass4.reserve(32);
lcd.setCursor(0, 0);
lcd.print(rand1);
lcd.setCursor(5, 0);
lcd.print(rand2);
lcd.setCursor(10, 0);
lcd.print(rand3);
lcd.setCursor(15, 0);
lcd.print(rand4);
lcd.setCursor(4, 0);
lcd.print('|');
lcd.setCursor(4, 1);
lcd.print('|');
lcd.setCursor(4, 2);
lcd.print('|');
lcd.setCursor(4, 3);
lcd.print('|');
lcd.setCursor(9, 0);
lcd.print('|');
lcd.setCursor(9, 1);
lcd.print('|');
lcd.setCursor(9, 2);
lcd.print('|');
lcd.setCursor(9, 3);
lcd.print('|');
lcd.setCursor(14, 0);
lcd.print('|');
lcd.setCursor(14, 1);
lcd.print('|');
lcd.setCursor(14, 2);
lcd.print('|');
lcd.setCursor(14, 3);
lcd.print('|');
}
void loop() {
if (code_pos == 0) {
char key = customKeypad.getKey();
if (key) {
Serial.print(key);
inputSequence[inputNumber] = customKeypad.getKey();
inputNumber++;
lcd.setCursor(inputNumber, 3);
lcd.print(key);
if (key == '*') {
lcd.setCursor(0, 3);
lcd.print(" ");
inputNumber = -1;
ipass = "";
}
else if (key == '#') {
if (rand1 == ipass) {
Serial.println("rand1 is correct");
lcd.setCursor(4, 3);
lcd.print("|");
lcd.setCursor(0, 1);
lcd.print("crct");
code_pos = 1;
}
else {
Serial.println("rand1 is incorrect");
lcd.setCursor(0, 2);
lcd.print("icrt");
lcd.setCursor(0, 3);
lcd.print(" ");
inputNumber = -1;
}
ipass = "";
}
else {
ipass += key;
}
}
}
if (code_pos == 1) {
char key2 = customKeypad.getKey();
if (key2) {
inputSequence[inputNumber2] = customKeypad.getKey();
inputNumber++;
lcd.setCursor(inputNumber, 3);
lcd.print(key2);
Serial.print(key2);
if (key2 == '*') {
lcd.setCursor(5, 3);
lcd.print(" ");
inputNumber = 4;
ipass2 = "";
}
else if (key2 == '#') {
if (rand2 == ipass2) {
Serial.println("rand2 is correct");
lcd.setCursor(9, 3);
lcd.print("|");
lcd.setCursor(5, 1);
lcd.print("crct");
code_pos = 2;
}
else {
Serial.println("rand2 is incorrect");
lcd.setCursor(5, 2);
lcd.print("icrt");
lcd.setCursor(5, 3);
lcd.print(" ");
inputNumber = 4;
}
ipass2 = "";
}
else {
ipass2 += key2;
}
}
}
if (code_pos == 2) {
char key3 = customKeypad.getKey();
if (key3) {
inputSequence[inputNumber3] = customKeypad.getKey();
inputNumber++;
lcd.setCursor(inputNumber, 3);
lcd.print(key3);
Serial.print(key3);
if (key3 == '*') {
lcd.setCursor(10, 3);
lcd.print(" ");
inputNumber = 9;
ipass3 = "";
}
else if (key3 == '#') {
if (rand3 == ipass3) {
Serial.println("rand3 is correct");
lcd.setCursor(14, 3);
lcd.print("|");
lcd.setCursor(10, 1);
lcd.print("crct");
code_pos = 3;
}
else {
Serial.println("rand3 is incorrect");
lcd.setCursor(10, 2);
lcd.print("icrt");
lcd.setCursor(10, 3);
lcd.print(" ");
inputNumber = 9;
}
ipass3 = "";
}
else {
ipass3 += key3;
}
}
}
if (code_pos == 3) {
char key4 = customKeypad.getKey();
if (key4) {
inputSequence[inputNumber4] = customKeypad.getKey();
inputNumber++;
lcd.setCursor(inputNumber, 3);
lcd.print(key4);
Serial.print(key4);
if (key4 == '*') {
lcd.setCursor(15, 3);
lcd.print(" ");
inputNumber = 14;
ipass4 = "";
}
else if (key4 == '#') {
if (rand4 == ipass4) {
Serial.println("rand4 is correct");
lcd.setCursor(19, 3);
lcd.print("|");
lcd.setCursor(15, 1);
lcd.print("crct");
code_pos = 4;
}
else {
Serial.println("rand4 is incorrect");
lcd.setCursor(15, 2);
lcd.print("icrt");
lcd.setCursor(15, 3);
lcd.print(" ");
inputNumber = 14;
}
ipass4 = "";
}
else {
ipass4 += key4;
}
}
}
}
This topic was automatically closed 180 days after the last reply. New replies are no longer allowed.