Start • Simple Video Signal • Video with the LPC2138 • Video Algorithm • Tricks Used • Vertical Sync & Resolution • Video for other Apps • Oscilloscope • Implementation • Construction & Results • Generate Video • Sources and PDF

VIDEO FOR OTHER APPS

The video-generating routines are located in the VideoController.c file posted on the Circuit Cellar FTP site. The critical fragments are written in assembler. The VideoController_Start(mode) function starts the video stream for a specified TV standard. (The parameter mode should be 1 for CCIR in Europe and 2 for RS-170A in the U.S.) When developing your own system, simply add the file to your project and call the function at the initialization section of your application. Use the VideoArray global variable for access to bitmap data. Just remember that the bitmap array has a half-word organization and is in big Endian format.

I also wrote a collection of helpful graphic routines that include general-purpose routines (e.g., drawing lines, text, wallpaper, and bitmaps) and specific functions (e.g., drawing a grid and printing stylized digits). All of the functions have comment headers. The fonts are also present there.