This board was developed for a
halloween costume. It is used to activate 20 LED panels (each with 96
LEDs) in any desired pattern. To restart the pattern sequence to its
beginning, the "RESET" button is pressed. To stop the current pattern
in the sequence and turn off all panels, the "NEXT" button is pressed.
Pressing the "NEXT" button a second time starts the next pattern in the
sequence.
The Gory Details: The heart of the board is a PIC, one of the most popular microcontrollers ever made. Though each line of a PIC can drive one or two LEDs directly, 96 would be a bit much. The lines each therefore have a buffer transistor (the small black parts near the top and bottom edges) which permit the line to control half an amp.
The LED panels used have all their positive connections tied to a 12V source. The negative connection of each board is tied to one of the numbered solder points near the transistors. Whenever a PIC line drives out a '1', the associated transistor turns on and connects the solder point to ground, which is the massive ring around the perimeter of the board. The panel then has 12V and lights up.
This board is a "simple" level project.
The Gory Details: The heart of the board is a PIC, one of the most popular microcontrollers ever made. Though each line of a PIC can drive one or two LEDs directly, 96 would be a bit much. The lines each therefore have a buffer transistor (the small black parts near the top and bottom edges) which permit the line to control half an amp.
The LED panels used have all their positive connections tied to a 12V source. The negative connection of each board is tied to one of the numbered solder points near the transistors. Whenever a PIC line drives out a '1', the associated transistor turns on and connects the solder point to ground, which is the massive ring around the perimeter of the board. The panel then has 12V and lights up.
This board is a "simple" level project.