**It’s not technically or legally possible to do real cryptocurrency mining with an Arduino.**
Here’s why:
* Real mining (like Bitcoin, Ethereum, etc.) requires **massive computational power (hashing billions of SHA-256 or Ethash operations per second)**.
* An Arduino’s microcontroller (like the ATmega328 or ESP32) can do **only a few thousand operations per second**, which is **billions of times slower** than what’s required.
* So even if you try, you would consume power but earn **zero reward** — you’ll never find a valid block.
However — you **can simulate** crypto mining on Arduino as an educational project to understand the concept (hashing, difficulty, nonce finding, etc.).
---
### ✅ Example: **Simulated Bitcoin Miner (Educational Only)**
This code *mimics* mining by calculating SHA-256 hashes and finding one with a specific number of leading zeros.
cpp
#include <SHA256.h> // You may need to install a SHA256 Arduino library
SHA256 sha256;
String blockData = "Hello Blockchain";
unsigned long nonce = 0;
String hashResult;
int difficulty = 3; // Number of leading zeros required
String toHexString(uint8_t* data, int len) {
String s = "";
for (int i = 0; i < len; i++) {
if (data[i] < 16) s += "0";
s += String(data[i], HEX);
}
return s;
}
void setup() {
Serial.begin(9600);
Serial.println("Starting simulated mining...");
}
void loop() {
String input = blockData + String(nonce);
sha256.reset();
sha256.update((const uint8_t*)input.c_str(), input.length());
uint8_t* hash = sha256.result();
hashResult = toHexString(hash, 32);
// Check if hash meets difficulty target
bool valid = true;
for (int i = 0; i < difficulty; i++) {
if (hashResult[i] != '0') {
valid = false;
break;
}
}
if (valid) {
Serial.print("Block mined! Nonce: ");
Serial.print(nonce);
Serial.print(" Hash: ");
Serial.println(hashResult);
delay(5000); // Pause to show result
nonce = 0; // Reset for demonstration
} else {
nonce++;
}
}
---
### ⚙️ How this works:
1. It concatenates some **data + nonce**.
2. Computes the **SHA-256 hash**.
3. Checks if the hash has the required **number of leading zeros**.
4. Keeps incrementing the nonce until a valid hash is found — similar to proof-of-work.
---
### 📦 Required Library:
Install a lightweight SHA256 library:
* Open **Arduino IDE → Sketch → Include Library → Manage Libraries → Search “SHA256” → Install**
(for example: “Crypto” by Nicholas Clark or “ArduinoHash”)
