The document describes a music visualizer project that uses a microcontroller and various hardware components to analyze an audio signal and produce a reactive light display in response to the music. It reads the audio signal, uses an MSGEQ7 chip to split it into frequency bands, processes the signal data to extract levels for each band, and interfaces with LED strips to create a visualization of the equalizer levels through changing light patterns. The goal is to create an enhanced visual experience for the listener by synchronizing colors and patterns on the lights with the music.

1. MUSIC VISUALIZER
PROJECT BY:
MATT HOWA

2. OBJECTIVES
• Read audio signal and process useful data
• Connect to MSGEQ7 chip to split audio signal into Highs, Mids,
Lows
• Create a reactive light display
• Interface with DotStar Light Strips for a more enhanced display
• For Saturday: Interface with an LED Matrix to create a running
equalizer

3. HARDWARE
• stm32F0 Discovery board
• Audafruit Trinket Pro
• 3 x MOSFET
• MSGEQ7 chip
• Dotstar LED strip
• RGB LED strip

4. MSGEQ7
• Frequency Splitter
• Seven Band Graphic
Equalizer

5. SIGNAL PROCESSING
• Read ADC
• Compute a Running Average
• Normalize using Min/Max
• Apply Gain
int smoothing(){
total = total - readings[readIndex];
readings[readIndex] = analogRead(A0);
if (maxx < readings[readIndex]){
maxx = readings[readIndex];
}
if (minn > readings[readIndex]){
minn = 0;
}
total = total + readings[readIndex];
readIndex = readIndex + 1;
if (readIndex >= numReadings) {
readIndex = 0;
}
// calculate the average and applies gain
average = (total) / numReadings;
normal = (double)average/((double)maxx );
OPT = normal*gain;
int dump = (int) OPT;
return dump;
}