Why Arduino, and not 555?

A project log for nRF_Detekt

This project is meant as a security add-on to an individual's physical security. Will warn of intruders in real-time and while you are away.

int-mosfetInt-Mosfet 05/21/2016 at 03:130 Comments

This is a bit of a not-so-inside joke at Hackaday. If you use a device that is seemingly overpowered for the application, you always have someone chime in they could do it with less. In the real-world, sometimes you have products that are really successful and eventually you run out of code space on your chip from accumulated features or they go EOL (end of life) and you have to migrate to another chip. More often then not, the commenters can't link to their project where they actually do this (if they do, it most likely has considerably less features), and we all get on with our lives.

But seriously, why Arduino here?

I'm using Arduino because I want to increase security for those that can't otherwise make their own homebrew security products in the easiest way I see fit. That's the main reason. Also why I'm using the Uno board, it's the most popular Arduino board. There's a big community around the Arduino too so it's fun to make stuff to add to all the contributions others have made. To be clear, connecting an NRF module to an Arduino is not novel whatsoever, but I haven't seen anyone make exactly what I'm doing, otherwise I'd just build their project.

I wanted to make a small security device that can log evidence of physical break-ins to homes, labs, offices, etc.; that the user can program (because otherwise you're trusting a blackbox, backdoors are a constant worry in security and sometimes they can go so deep even most engineers can't mitigate them).

So I was planning this out for a while, and when I had a few spare moments over winter break (January 2016) I put together the first working version.

This website was a big help in getting started, especially pinouts. I will list the pinouts I'm using in future logs (may happen after May 30th). They're all the same except for CE and CSN (which is 9 and 10 for me).

The next site is linked on my github (where most of my technical changes will be, since this project is more code than hardware changes). This library is the main code behind interfacing the NRF module and the Arduino. It was a huge help and is a great library. I modified a starting example as a starting point for the project.