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README.md

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+# Arduino Powerbank Keep-Alive + Daily Reset Counter
+
+This project uses an Arduino, a DS3231 real-time clock (RTC), buttons, LEDs, and a resistor to:
+
+- Keep a USB power bank **awake** by periodically pulsing a load on a digital pin.
+- Control 4 LEDs with 4 buttons (toggle on/off).
+- Remember LED states across power loss using EEPROM.
+- Automatically reset all LEDs every day at 12:00 PM.
+
+***
+
+### Features
+
+- **Silent keep-alive:**
+Periodic pulse on a resistor connected to pin 6 so power banks don’t auto-shutoff.
+- **4 independent channels:**
+4 buttons control 4 LEDs (via a mapping array), each toggling its own state.
+- **Persistent state:**
+LED on/off states are stored in EEPROM and restored on startup.
+- **Daily auto reset:**
+At exactly 12:00:00 PM (noon), all LED states are cleared and saved as off.
+
+***
+
+### Hardware Requirements
+
+- Arduino (e.g., Uno, Nano, Pro Mini)
+- DS3231 RTC module (connected via I²C: SDA/SCL)
+- 4 momentary push buttons
+- 4 LEDs with appropriate current-limiting resistors
+- 1 additional resistor as keep-alive load (between pin 6 and GND)
+- USB power bank (optional but typical use case)
+- Jumper wires and breadboard or PCB
+
+***
+
+### Pinout
+
+- Buttons (with internal pullups):
+    - Button 1 → pin 2
+    - Button 2 → pin 3
+    - Button 3 → pin 4
+    - Button 4 → pin 5
+- LEDs:
+    - LED 1 → pin 8
+    - LED 2 → pin 9
+    - LED 3 → pin 10
+    - LED 4 → pin 11
+- Keep-alive resistor:
+    - One side of resistor → pin 6
+    - Other side of resistor → GND
+- RTC (DS3231):
+    - SDA → Arduino SDA (A4 on Uno)
+    - SCL → Arduino SCL (A5 on Uno)
+    - VCC → 5 V
+    - GND → GND
+- Onboard LED (pin 13) is explicitly disabled.
+
+***
+
+### Libraries Used
+
+Install the following via the Arduino Library Manager:
+
+- **RTClib** (by Adafruit)
+- **EEPROM** (included with Arduino core)
+- **Wire** (included with Arduino core)
+
+Include them in your sketch:
+
+```cpp
+#include <Wire.h>
+#include <RTClib.h>
+#include <EEPROM.h>
+```
+
+
+***
+
+### How It Works
+
+1. **Setup phase**
+    - Initializes the DS3231 RTC.
+    - Sets pin 6 LOW and disables the onboard LED on pin 13.
+    - Configures button pins with `INPUT_PULLUP`.
+    - Configures LED pins as outputs and restores each LED state from EEPROM.
+2. **Keep-alive pulses**
+    - Every `pulseInterval` milliseconds, pin 6 goes HIGH for `pulseDuration` milliseconds, then returns LOW.
+    - Default values in the code:
+        - `pulseDuration = 800`
+        - `pulseInterval = 10000`
+    - Adjust these if your power bank requires a different pattern.
+3. **Button handling**
+    - Buttons are active LOW (because of `INPUT_PULLUP`).
+    - On press:
+        - Debounces with a 50 ms delay.
+        - Uses `ledMap[]` to map button index to a specific LED index.
+        - Toggles that LED’s state, writes it to EEPROM, and waits for the button to be released.
+
+Example mapping from code:
+
+```cpp
+const int ledMap[] = {3, 1, 0, 2};
+```
+
+This means:
+    - Button on pin 2 controls LED index 3 (pin 11)
+    - Button on pin 3 controls LED index 1 (pin 9)
+    - Button on pin 4 controls LED index 0 (pin 8)
+    - Button on pin 5 controls LED index 2 (pin 10)
+4. **Daily reset at 12:00 PM**
+    - Reads current time from the DS3231 each loop.
+    - When time is exactly 12:00:00:
+        - If reset not yet done today, all LEDs are turned OFF and EEPROM is updated.
+        - `resetPerformed` flag prevents multiple resets within the same second.
+    - When time is no longer 12:00:00, `resetPerformed` resets to `false` for the next day.
+
+***
+
+### EEPROM Usage
+
+- EEPROM addresses 0–3 store the 4 LED states (`true`/`false` as bytes 1/0).
+- The code uses `EEPROM.update(address, value)` to avoid unnecessary writes.
+
+***
+
+### Setup Instructions
+
+1. Build the circuit according to the pinout.
+2. Connect the DS3231 and set the correct time once (e.g., using an example sketch from RTClib).
+3. Upload this sketch to the Arduino.
+4. Power the Arduino from your USB power bank.
+5. Press buttons to toggle LEDs; states will persist after power loss.
+6. At 12:00 PM every day, all LEDs will automatically reset to OFF.
+
+***
+
+### Configuration
+
+You can tweak these constants:
+
+```cpp
+const int pulseDuration = 800;   // ms HIGH time
+const int pulseInterval = 10000; // ms between pulses
+```
+
+- Increase `pulseDuration` if the power bank needs a stronger signal.
+- Decrease `pulseInterval` if it shuts off too quickly.
+
+***
+
+### Example Use Case
+
+Use this as a simple daily habit tracker powered by a USB power bank:
+
+- Each LED represents a daily task (e.g., exercise, reading).
+- Press the corresponding button when done; LED turns on and stays on.
+- At noon, all LEDs reset, ready for the next day, while the keep-alive pulse keeps the power bank from sleeping.
+
+***

arduino_logic.ino

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+#include <Wire.h>
+#include <RTClib.h>
+#include <EEPROM.h>
+
+RTC_DS3231 rtc;
+
+const int buttonPins[] = {2, 3, 4, 5}; 
+const int ledPins[]    = {8, 9, 10, 11}; 
+const int ledMap[]     = {3, 1, 0, 2}; 
+const int resistorPin  = 6; // RESISTOR GOES HERE (Pin 6 to GND)
+
+bool ledState[] = {false, false, false, false};
+bool resetPerformed = false;
+unsigned long lastKeepAlive = 0;
+const int pulseDuration = 800;   // 0.2s is usually enough to reset the timer
+const int pulseInterval = 10000; // 20s interval (test if your power bank handles this)
+
+void setup() {
+  rtc.begin();
+  
+  // Ensure the resistor pin starts LOW (off)
+  pinMode(resistorPin, OUTPUT);
+  digitalWrite(resistorPin, LOW);
+  
+  // Disable the onboard LED explicitly
+  pinMode(13, OUTPUT);
+  digitalWrite(13, LOW);
+
+  for (int i = 0; i < 4; i++) {
+    pinMode(buttonPins[i], INPUT_PULLUP);
+    pinMode(ledPins[i], OUTPUT);
+    ledState[i] = EEPROM.read(i); 
+    digitalWrite(ledPins[i], ledState[i] ? HIGH : LOW);
+  }
+}
+
+void loop() {
+  DateTime now = rtc.now();
+  unsigned long currentMillis = millis();
+
+  // --- 1. SILENT KEEP-ALIVE (PIN 6 ONLY) ---
+  if (currentMillis - lastKeepAlive > pulseInterval) {
+    digitalWrite(resistorPin, HIGH); 
+
+    if (currentMillis - lastKeepAlive > (pulseInterval + pulseDuration)) {
+      digitalWrite(resistorPin, LOW); 
+      lastKeepAlive = currentMillis;
+    }
+  }
+
+  // --- 2. BUTTONS ---
+  for (int i = 0; i < 4; i++) {
+    if (digitalRead(buttonPins[i]) == LOW) {
+      delay(50);
+      int targetLed = ledMap[i];
+      ledState[targetLed] = !ledState[targetLed];
+      digitalWrite(ledPins[targetLed], ledState[targetLed] ? HIGH : LOW);
+      EEPROM.update(targetLed, ledState[targetLed]); 
+      while(digitalRead(buttonPins[i]) == LOW);
+    }
+  }
+
+  // --- 3. DAILY RESET (12:00 PM) ---
+  if (now.hour() == 12 && now.minute() == 0 && now.second() == 0) {
+    if (!resetPerformed) {
+      for (int k = 0; k < 4; k++) {
+        ledState[k] = false;
+        digitalWrite(ledPins[k], LOW);
+        EEPROM.update(k, false);
+      }
+      resetPerformed = true;
+    }
+  } else {
+    resetPerformed = false;
+  }
+}