Wednesday, 28 November 2012

Nerf Stampeed electronics upgrade

This is a post I was going to make a little while ago about a fairly basic project to get me into Amtel's AVR microcontrollers... I had some problems with the internet on that day and have only just rediscoverd the draft that was saved :)



So I'm not happy with the stock electronics for the Nerf Stampeed. Using a 7 shot clip you can easily fire away all of your darts and still not hit anything. Also the 6 D cell batteries are a pain to replace and are massively heavy.

The solution:

Put a small microcontroller such as an Amtel AtTiny of some description, replace the current power switch with a 3-way switch to allow selecting between:
-Full Auto(Stock Setting)
-Burst(fires 2 or 3 darts at a time)
-Semi-Auto(fires 1 shot but automatically re-cocks)

Some way of displaying the number of rounds fired in battle and the battery level should be easy to set up. If I can find a way to differentiate between different magazines then a readout showing how many are left in the mag. would also be useful.

A display like this only needs an SPI interface, everything else can be controlled with digital I/O except for reading the battery state, the best solution for which I don't quite know right now but will probably need an ADC channel.

This is a fairly quick flowchart I did up showing the basic functions that will be called and when... not quite up to drawing a flowchart to show exactly how each function works... but I figure this is a start.

If you want to know why I did up a flowchart for this just ask me to put up the Qt code and flowchart that I taught myself and wrote in 1 week or so... the flowchart was about 2.5m high when printed so small it was barely readable... Originally I was trying to work it all out in my head... doesn't work that way... not like the simple little things they wanted me to do flowcharts for in my sfotware design and development course...