I have been sent a few things I will be using to make a prototype for the Halloween project. The main features will be playing audio on demand, and switching lights (or other 120V items) on and off in time to the audio. Here are the items I will be evaluating:
MP3 Shield ($19.99) from CutiDigi.com. This shield has its own flash storage and lets you load MP3 files over from SD memory cards or USB thumb drives. In addition to control buttons on the shield itself (vol+/-, pref, next, play), it also has buttons to start up the copy operation and put the unit to sleep. There is a 1/8″ headphone style jack for getting audio out. It is controlled via serial (tx/rx) and can be made to play a specific track number off the memory.
Relay Shield ($7.59) from e-Bay seller happyvalley009. This shield has four relays that can handle 120V up to 3amps, which is a small amount but enough for our needs. It is dangerous to run 120V in to a shield like this, as a short could really cause some problems. A better solution might be to use a separate relay board ($8.49 with Amazon Prime shipping) that is controlled without being attached to the Arduino itself. That would let it be physically separate and still be controlled the same way (and, this one can handle more amperage).
As soon as my funding source returns from vacation, we will order more items and begin working on a prototype.
For those who wish to follow along with my Pac-Man project without having to copy/paste source code from these articles, I have posted my current work-in-progress source (which includes many changes I have not discussed, yet).
I have broken the program up in to multiple files, but since this makes quite a mess in the IDE, I am probably going to combine all the bitmaps in to one file instead of separate ones.
If you want to play with it, you can modify the Joystick code to read whatever you have for input (buttons, analog joystick, whatever) and at least move the Pac-Man around the screen. There is no ghost collision detection, no scoring, and no dot handling yet… But it’s a fun demo.
I am finally getting around to posting some of my Arduino sources to GitHub. It may be awhile before I get everything updated, but I will at least try to get most of my work-in-progress versions out there for folks to look at.