web3-arduino

• What is this library?

  • This is an Arduino (or ESP32) library to use web3 on Ethereum platform.

• What is Arduino?

  • Arduino is an open source computer hardware and software.
  • https://www.arduino.cc/

• What is ESP32?

  • ESP32 is a series of low cost, low power system on a chip microcontrollers with integrated Wi-Fi and dual-mode Bluetooth.
  • https://www.espressif.com/en/products/hardware/esp32/overview

• What is web3?

  • Web3 is the Ethereum compatible API which implements the Generic JSON RPC spec. Originally Javascript version is developed.
  • https://github.com/ethereum/web3.js/

• What is Ethereum?

  • Ethereum is a decentralized platform for applications that run exactly as programmed without any chance of fraud, censorship or third-party interference.
  • https://www.ethereum.org/

Environment

• Confirmed device
  • ESP-WROOM-32
• Used Ethereum client
  • INFURA (https://infura.io)

Installation

1. download the zip file from Clone or download button on Github.
2. launch Arduino IDE.
3. Install board settings ESP32-Arduino
4. Sketch -> Include Library -> Add .ZIP file -> select downloaded zip file.
5. Then you can use this from Arduino IDE.

Example

Please refer examples directory to learn more about how to use the libraries

Setup

#define INFURA_HOST "rinkeby.infura.io"
#define INFURA_PATH "/<YOUR_INFURA_ID>"

Web3 web3(INFURA_HOST, INFURA_PATH);

Generate a private key

python -c 'import os; print ", ".join([ str(ord(c)) for c in bytes(os.urandom(32)) ])'

Copy this to terminal and paste the output as your private key in the ino file.

To convert this to a private key you can use in MyEtherWallet you do: print ''.join('{:02x}'.format(x) for x in array_alpha)

Dependencies

• cJSON
• secp256k1
• ESP32-Arduino