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.
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.
Step 1: The "Firecracker" Circuit
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.