Instructables
Picture of Control the real world from your project.
Recently,. I wrote an Instructable called, "Connect your projects to the Internet".  
In that Instructable, I demonstrated the use of Microchip's ENC28J60 chip to connect your Propeller micro-controller to the Internet.   This time, I want to carry things to the next step with an easy way to control the "real world" from your project.

We'll be looking at a method to safely connect 110v devices to the Propeller through the use of the x10 firecracker, a device which accepts "serial" data to wirelessly control up to 256 different devices.   Later in this instructable, I'll tie the project together with the Microchip ENC28J60 project, propelling it to an Internet controllable system.

Parts List
1 - Propeller Platform board (or equivalent Propeller based board)
1 - E-Net Module (or equivalent ENC28J60 circuit)
1 - A breadboard or PCB.  I'll talk about methods for both.
1 - An x10 firecracker kit (Ebay), (X10.com)

1 - A "TC4427CPA" chip (Digikey)
1 - 9pin male dsub connector (Radio Shack)
2 - 10k resistors (Radio Shack)
Some hookup wire and a few basic tools.



 
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Step 1: The "Firecracker" Circuit

Picture of The
The circuit for controlling the x10 Firecracker is surprisingly very simple.  
This is the perfect project for a beginner, as it involves a single chip and a couple "pull down" resistors.

The x10 firecracker isn't actually a "serial communication" device like a modem, but rather accepts data from the micro-controller by reading bit sequences from the DTR/RTS lines.   The Propeller can easily send data on these lines using a TC4427 level-shifter.

Jon McPhalen (Parallax forums) came up with this amazing circuit.

There are a couple different demonstration programs which allow the firecracker module to be controlled by the Propeller using a serial terminal:

Jon McPhalen's: JM_Firecracker_Demo
Ron Czapala's: FC_Demo

Both of these simple demonstration programs are excellent examples of what is possible with a few lines of Propeller Spin code.

Great Instructable, Just 1 question in the schematic for the level shifter where does the +v go ? 5V wouldn't make sense ...
spike35792 years ago
Thanks so much for taking the time to put your projects up. They are written at just the right level for people(me) inexperienced in electronics hardware to get a grasp of how to do some really interesting and useful projects. I haven't made any of them yet but it is great to follow along and learn. Keep up the good work!
We all start out inexperienced. The only way I've ever found to get experience is to start out though. As much electronics experience as I have, when I make something I've never made before none of it helps me much. A little I guess, but not as much as I'd think it would.
pfred22 years ago
I have this stuff. I use it to turn a light on and off in my bedroom. Sometimes the light turns itself on and off. I keep on meaning to change the channel I'm on hoping that maybe it'll stop doing that. I never used the computer serial dongle thing. I just use the remote, the wired controller, and one of the modules as sort of a 3 way switch.

It's nice, I can turn the light on as I go into my room, then turn it off when I'm in bed. One of these days I should just put in a couple real switches to do what I'm doing.