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|< ALT="" BORDER=0 height=16 width=13 align=ABSBOTTOM>INTERNET PIC 2000 CONTEST WINNERS|
INTERNET CONNECTIVITY CATEGORY WINNERS
To meet the requirements of the Internet Connectivity category, contestants had to invent a new way for TCP/IP connectivity implementation other than the Microchip AN724 (or other previously published in Circuit Cellar) and incorporate additional protocols such as HTP, UDP, FTP or TFTP, IRC, and/or SMTP. The project could connect directly or via modem.
FIRST PRIZE WINNER
The home automation industry is dominated by a standard known as X10. Devices that are compatible with this product line are sold by outlets such as Radio Shack and Sears making them widely available to the general public. These units communicate over the existing power line wiring to control all sorts of loads such as lamps and appliances. A simple powerline modem is also obtainable that will allow a computer to send and receive these commands. The PIC X10 Web Server combines a web server and an X10 controller. With this project, any user can control and monitor over the web the status of their home or office environment that has been equipped with X10 units.
A significant difference from previous PIC based Web Servers  is the Ethernet interface, making this the first direct Internet connected PIC known to the author. This project is similar to the PicoWeb Server  except for several differences:
• The maximum file size is not limited to one Ethernet packet (1400 bytes). This complicates software considerably as more of the TCP/IP stack needs to be implemented.
• The need for the 16 KB of external RAM is eliminated as all code fits in the PIC’s onboard resources.
The PIC obtains its Ethernet interface via a standard NE2000-compatible Ethernet card. It is plugged into an ISA connector on the printed circuit board that holds the PIC. The PIC emulates a PC ISA interface to communicate with the Ethernet card.
After the X10 Web Server is connected to the local LAN, any user can communicate with the server by using the URL http://IP_ADDRESS, where "IP_ADDRESS" is the preselected IP Address of the web server. Photo 2 shows an example of the resultant display on the browser.
The user can check the status of the units and can also click on the hyperlinks to send commands to control the loads (which will update their status). If any other controller sends a command to the load, its status is also automatically updated in the home control panel.
The control panel can be reconfigured if the user clicks on the "Config" button at the bottom of the main control panel. The resultant display is shown in Photo 3.
To add a unit, the user simply enters the X10 address (in this example "A1") and its name ("Room") and then clicks "Add." The user is then returned to the main auto-loading home control panel with the new unit added (its status will be displayed as "?"). Similarly, clicking on "Delete" after entering a unit number causes that unit to be deleted from the control panel. The names and the status of up to 16 units are preserved in the PIC’s nonvolatile EEPROM.
This powerful and compact web server should be a useful addition to any environment requiring the capability to send and receive X10 commands without needing the installation of any unusual hardware or software.
 The X10 company, http://www.x10.com
 Serial-line PIC web server, http://www-ccs.cs.umass.edu/~shri/iPic.html
 PicoWeb Server, http://www.picoweb.net
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