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Abstract
For our final project in Computer Architecture we decided to build an FPGA Guitar PedalBoard. Pedalboards are boards that connect to electric guitars and house several different effects pedals. Effect pedals are used to modify the sound of electric guitars and there are several different types of effects. For instance there are octave pedals that raise or lower the octave played, and distortion pedals that distort the sound produced by the guitar.
For our pedalboard we used the switches on the FPGA to act as different pedals. When a switch is raised a certain effect is applied to the song that we play through a speaker attached to the FPGA. We choose to implement two effects, octave changes and distortion.
Reasoning
This project allowed us to explore an interesting application of the FPGA. Amanda is an avid musician and enjoyed being able to connect Computer Architecture back to her hobbies. This particular project was great because it could be easily scaled up or down depending on the amount of work that we were handling.
Our System
[INSERT SCHEMATIC OF SYSTEM]
Sound
In order to produce notes our system manipulates a clock. A variable commonly referred to as a clock divider is used to split the clock cycle. Depending on the value of the clock divider the cycle the wave reaches a different frequency creating different notes.
In our code the divider is compared against a counter that counts the number of clock cycles. Once it has reached the requisite number of cycles it switches the value of the output.
Octave Changes
