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Kevin's Halloween 2008 Projects
For my 2008 Halloween project I created 8 digital candle circuits which each contain 9 LED lights on them (3 yellow, 3 red, and 3 blue). All the candles wire together onto a RS485 network which then hooks up to a computer. A computer program can then address the candles individually or all at once to tell them to flicker yellow, red, or blue. It can also have the candles flip on any of the colors without flickering or just flip on all the LEDs. My original intention was to animate the pumpkin lights to music which is now slated for next year being that the firmware and control software needs some tweaking to make them fast enough to stay in sync with the music. At least now I know part of what I'll be doing next year!
Sat Oct 04 00:00:00 EDT 2008

To describe what is going on in this picture

- I would first send command messages for the candle via RS232 serial signal from the computer to the small board on the left which would convert it to a RS485 signal so it could be broad cast to all the candles throughout my dungeon.

- An RS485 signal travels from the converter (small board on the left) to the larger board on the right which is my led candle prototype.

- Then on a temporary basis I have debug messages sent via TWI serial interface from the candle prototype(large board on the left) to the circuit for debugging purposes (large board in the top right).

- That board then sends the debug messages via RS232 back into the computer to display on a terminal screen.

This may not have been the best way to do this, but it sure was fun seeing if I could make it work. All that being said on my next project I really need to figure out how to properly debug Atmega microcontrollers.

Sun Oct 05 00:00:00 EDT 2008

Well my crazy debugging scheme worked well enough to allow me figure out how to send a command to my candle from my computer to tell it to start flickering yellow.

Here is my candle prototype flickering blue after transmitting it the appropriate command.

Thu Oct 16 00:00:00 EDT 2008

Now for the mad rush. I should point out that all of this construction is happening the night before my Halloween party. At the bottom of the picture you can see my first completed candle. Laying circuitry out on a breadboard is obviously not the same as laying out a circuit for a production model so I had to build one first to see how it would go. I decide to just to use some prototyping board from radio shack to build my 8 candles. It would have been better to create a pcb for these, but I hadnt done that before and I definitely didnt have time with less than 24 hours till party time.

Here is a closer look at my completed first model.

Here are a few of the remaining 7 halfway completed with some of the components on the board.

Fri Oct 17 00:00:00 EDT 2008

Here are the 7 candles almost done. That was one night with a heck of a lot of soldering.

Here is one of the completed candles up close.

Here is the bottom of one of the completed candles.

Here is an overview of the entire design of the pumkins.

Here is the schematic for the candles. I doubt if it is that good Its the first real schematic that I have ever put together. I created it in eagle CAD.

This is just the simple power supply for both the converter and each candle. I put a power supply on each candle so I could increase the voltage on the lines running to the candles to compensate for the longer runs if necessary.

Here is the schematic for the RS232 to RS485 Converter. I used this to connect the Pumpkin Network to my computer. I would send commands out the RS232 port on my computer into this thing. The commands would then get converted to RS485 signals and broadcast to all the pumpkins. This version currently does not support two way communication. I only needed to tell the pumpkins what to do.?