FPGA Tuner

FPGA Tuner using Xlinix FFT and Audio Codec
[WARNING: LOUD NOISES]

Thanks to Mike Field of Hamsterworks for providing program files for the Audio Codec
You can find his code here:

You can see the code for the FFT implementation here:

ECE 524 Final Project
California State University, Northridge (CSUN)

Vivado 2017 FFT Core / ADAU1761 Audio Codec

NOTE: This demo was done as proof of concept for the next step in video2.
The sampling was done at 100MHz in order to reduce time of synthesis/simulation
and latency. For that reason the FFT acts nearly instantaneous to the eye and the lights
change upon FFT input change with the switches.

This video shows the functions of the FFT with frequencies of:

122070 Hz
134277 Hz
146484 Hz
158691 Hz
170898 Hz
183105 Hz
195312 Hz

This corresponds to bins 10/11/12/13/14/15/16 of the FFT @:
8192 transform length
100 MHz sampling frequency

The LEDS light as such:
BIN / PIN
10 / LD7
11 / LD6
12 / LD5
13 / LD4/3
14 / LD2
15 / LD1
16 / LD0

This implementation would be for checking whether the frequency was approximately 158691 Hz.

-- video2_tuner-test --

ECE 524 Final Project
California State University, Northridge (CSUN)

Vivado 2017 FFT Core / ADAU1761 Audio Codec

This video shows the functions of the FFT and audio codec with the standard tuning
frequencies for 6-string guitar:

Note / Octave (Frequency)
E4 (329.63 Hz)
B3 (246.94 Hz)
G3 (196.00 Hz)
D3 (146.83 Hz)
A2 (110.00 Hz)
E2 (82.41 Hz)

E A D G B E

The middle 2 LEDs LD4/LD3 should light for each audio input.

Due to the latency of the FFT at the sampling frequency of 48kHz, the FFT
output changes after 1.6s.

NOTE: The demo in this video was made as a test and not for presentation purposes
so the output LEDs cannot be visually verified for all cases as the input cases were changed
faster than the FFT functions.