Keypad

Introduction

This is the Hackerspace Warsaw electronic lock mk2 project.

Work in progress! This is a prototype for a TP-Link WR703n based hardware solution - with a I2C bus on which there is a MAX7300 IO expander and a PN532 NFC tag reader. The I2C is software bit-banged by the kernel, drivers for both the IO expander and the PN532 are written in Lua.

Overview

The hacklock is mae out of two separate pieces of hardware:

• The main lock unit, which runs Linux on a low-power SoC, has one I2C bus to communicate with an NFC reader and some GPIO, and a second I2C bus to communicate with:
• The keypad, which is a 10-key (or more) physical keypad attached externally, and is based around and ATMega8 uC (they're cheap!)

Current hardware status

Right now the project is in a prototype status. The keypad part is nearly identical to what will be in production, except that the PCB is home-etched.

The main lock part itself is however based on a TP-Link WR703N router with OpenWRT and a software I2C bus. In the future, it will probably be replaced woth a custom i.MX233-based 4-layer board.

Files

• software/
  • main/ - code for the central unit of the lock
    • main.lua - main Lua script
    • lua-libs/ - other Lua libraries
      • mips-bin/ - C libraries compiled for MIPS/OpenWRT
      • luai2c.tar.gz** - C i2c library source
      • luasha2.tar.gz - C sha2 library source
  • keypad/ - AVR code for the keypad
    • Makefile - the makefile for the keypad firmware
• hardware/
  • keypad/ - KiCAD files for the keypad PCB

Hacking

Feel free to hack around. The whole project, however, is not anywhere near release, so things will change around and probably make no sense at the moment.