Results

The system performs according to specifications. The output sound quality is excellent, with the exception of the mute function. When mute is activated, the output of the analog multiplexer is a floating node and is subject to high frequency noise. However, when an audio device is activated, the noise disappears, even if the input audio source is not playing.

Multiple LCD panels can be run off of the same microcontroller port with minimal additional hardware and software control. The LCD panel bug that normally prevents the use of the last 8 characters on the display was solved. The bug lies in the addressing scheme the panel uses for its characters. Instead of being a 16x1 panel, it acts as an 8x2 panel. Therefore, to write a full 16 character line, the first 8 bits must be written starting at x,y (0,0) and the last 8 bits must be written starting at x,y (0,1).

The IR transmission scheme works flawlessly, with minimal memory overhead for storage of the IR codes and simple software to control the transmission of the codes. Although the system is designed for the IR emitters to be placed in direct contact with the audio equipment, they function from over 5 feet away and can be successfully reflected to the source.

The Winamp plugin successfully receives commands from the microcontroller across the UART connection. In addition, it can transmit the song title to the microcontroller, which then displays it to the LCD panel. The plugin has proven to work on a Windows 2000 platform, but does not function properly on Windows 98.