---

Main Program:

• loop
  • Calls the nextLayer() member function of the Multiplexer class on a preset interval
  • While we wait for the next layer to be drawn, the loop calls the subtasks() function to perform several smaller tasks required to draw the matrix
• subtasks
  • Each subtask referenced in this function is called once for every complete matrix that is sent to the cube. The function must be reset after every iteration
  • The first step (case 0) is calling the checkVolume() member function of the MSGEQ7 class, this decides whether the subtasks function draws a volume matrix or a spectrum matrix
  • Next, we collect the data required to construct the matrix. This is only required if we are drawing a spectrum matrix
  • Then, we construct the matrix itself. This is handled entirely by the respective classes
  • Lastly, we queue the matrix we just drew, meaning that it will be shown in the next iteration of the loop

Multiplexer Class:

• setMatrix
  • Uses memcpy to either queue a new matrix or allow the queued matrix to be shown
• nextLayer
  • Handles the drawing of individual layers and the queuing of matrices
  • First, calls the constructData() function to format the data in a way that the registers will understand
  • Then, calls the sendData() function to send the data to the cube
• constructData
  • A helper function for nextLayer() that handles the mapping of output pins and the conversion of the resultant binary array to an integer array
• sendToCube
  • Uses the SPI bus to send the data from the constructData() function to the shift registers

MSGEQ7 Class:

• getSpectrum
  • Reads data from the MSGEQ7 breakout board using analogRead()
• normSpectrum
  • Takes the array from the getSpectrum() function and converts from 7 channels to 36
• makeSpectrumMatrix
  • Maps each frequency band to a specific column of the cube
  • Applies a threshold to the raw reading to decide how many LED’s to light in each column and constructs a Boolean matrix based on this data
• queueMatrix
  • Calls the setMatrix() member of the Multiplexer class to queue the matrix that was built by the makeSpectrumMatrix() function

VolumeControl Class:

• checkVolume
  • Uses a timer and the getVolume() function to decide whether or not to draw a volume matrix
• getVolume
  • Reads data from the volume potentiometer and normalizes the reading
  • Creates a running average of the normalized readings
• makeVolumeMatrix
  • Takes the current volume reading and creates a Boolean matrix that displays the volume as front-to-back bars that ascend each column then move from left to right to the next column
• queueMatrix
  • Takes the matrix that was constructed by the makeVolumeMatrix and queues it to be shown on the cube