Issue 151 February 2003
Working the ’Net

FRESHEN UP

The SitePlayer package is reasonably friendly and easy to use, all the more so by virtue of some handy utilities that streamline development. The standard flow is to define your variables and such in the aforementioned SitePlayer definition file (.spd) and then create your web page using a combination of web-authoring tools and tweaking the resulting HTML. Put the HTML and all other files associated with your SitePlayer web site (e.g., the seven-segment LED .jpg files and any other graphics) in a folder and call up the SiteLinker program.

SiteLinker chews on your web site folder and spits out a SitePlayer binary (.spb) file that’s downloaded into the ’51’s flash memory via the network. Refresh your web browser to see the results and repeat the cycle as necessary.

As I mentioned earlier, SitePlayer web sites are limited to 48 KB by the confines of the ’51’s on-chip flash memory. That means you have to be careful about going overboard with fancy graphics, long file names, and so on. The good news is that the 48-KB limit translates into a reasonably quick link-download-reflash cycle that takes only 20 to 30 s.

Nevertheless, even a relatively minor delay inhibits the quick iteration that’s called for by the artistic exercise of creating a web page, not to mention the tweak-and-try personality of the SitePlayer tools. To that end, the SitePlayerPC utility provided essentially turns the PC into a big SitePlayer, allowing you to run your web site .spd binary file in situ.

Similarly, the serial tester utility allows development to proceed using the PC COM port as a stand-in for the embedded device that ultimately will be connected to the SitePlayer’s serial port. The utility allows easy access (GET and PUT) to SitePlayer objects. It also displays the commands and responses traveling across the serial link, which is valuable assistance when you’re writing the serial interface code that runs on your own device.