The RC-4 Controlled Christmas TreeThis Project was submitted by Parallax's own Ryan Clarke
When the EFX group released the RC-4 relay controller board, they opened the door to some really cool applications. Now it is possible to control AC loads as easily as LEDs. It being the holidays, I decided to build boxes to control the lights on Katie and my Christmas Tree. I picked up some fairly inexpensive plastic boxes, the kind used to hold wall jacks. The boxes were designed for four AC outlets:
4 plug plastic box
Since each RC-4 board can control up to four relays, I decided that each ‘brick’ would hold four outlets and a single RC-4. The boxes could then be chained together, but grouping them like this would provide the most flexibility so that I could easily reuse them for other displays and projects.
Since these will be plugged into home AC lines, I used 14 gauge wire where possible. I had decided that I would be making three of these bricks, so I needed six outlets. Here you can see the neutrals of each tied together:
Neutrals tied with 14 gauge wire
After connecting the neutrals together I attached wires to each of the plugs (because I wanted individual control of each jack). The jacks come with the top and bottom tied together, so I had to remove the connection for the switched side, allowing for individual control of each jack. Then I mounted them in the boxes:
Outlets mounted into boxes
The next thing to do was add the RC-4s into the mix, connecting each jack to a terminal in the RC-4, and adding wire out the other side of each terminal:
Jacks connected to RC-4 board
Adding the extension cord to complete the connection for power, and adding connectors to complete signal lines to control the RC-4 finished the boxes:
Finished boxes
The tree hid the bricks, even though the red LEDs on the RC-4 are quite the show in and of themselves:
Bricks behind tree
The finished tree:
Bricks behind tree
When I put the lights on the tree, I did horizontal bands and stripes from top to bottom. With a Basic Stamp 2 microcontroller I have individual control over each individual strand. The project produced great results in animating the lights on the tree.
In total this project used 3 RC-4s, 10 relays (room for 12), a BS2SX and a BOE. |