Simple Audio Processing

This repository includes artefacts that I created in the course of doing tutorials 17 to 21 from https://www.beyond-circuits.com/wordpress/tutorial/

Overview

The instructions below describe artefacts that are present in this repository and process of building and deploying the resultant application to ZedBoard. The instructions were created with the following in mind:

Hardware:

ZedBoard Rev. D
source of audio connected to ZedBoard's Audio Jack Line In (BLUE).
headphones connected to ZedBoard's Audio Jack Headphone Out (BLACK).

Software:

Ubuntu 16.04 LTS
Vivado 2018.1

Layout

The layout of the repository is as follows:

pl/ - artefacts relevant to the Programmable Logic - of the most importance are:
    ip_repo/ - location of IP source files .
        user.org_user_i2s_receiver_1.0/ - i2s_receiver.
        user.org_user_axi4_stream_delay_1.0/ - axi4_stream_delay.
        user.org_user_adau1761_controller_1.0/ - adau1761_controller.
        user.org_user_i2s_transmitter_1.0/ - i2s_transmitter

    src/ - source files that are not IPs.
        constraints/
            audio-processing.xdc - constraints file.
        verilog/
            sample-scaler.v - Verilog source for scaling samples to different sample widths.
            audio_processing_wrapper.v - Vivado generated wrapper that instantiates relevant modules.

ps/ - artefacts relevant to the Processing System - there is only one file there:
    audio-processing.c - functionality for initialising ADAU1761 audio codec.

README.md - this file.
recreate-project.tcl - Tcl script for creating Vivado project.
audio-processing.pdf - block diagram of the system.
audio-processing.3gp - video clip where the running system is presented.

Building and Executing

In terminal, go to folder with git clone of this repository (./).

Execute:

$ vivado -mode batch -source recreate-project.tcl

If successful, you should see the following message from that execution:

INFO: Project created:audio-processing

Open the created Vivado project (./audio-processing/audio-processing.xpr) in Vivado with File > Project > Open.
In the Flow Navigator panel find and select Generate Bitstream.
After the generation completes select File > Export > Export Hardware....

Make sure that the check box Include bitstream is selected.
Launch SDK with File > Launch SDK.
Within the SDK/Eclipse go to File > New > Application Project, for project name select audio-processing, and make the project Empty Application.
Back in the terminal change your working directory as follows:
```
$ cd ./audio-processing/audio-processing.sdk/audio-processing/src
```
and create a softlink to ps/audio-processing.c there, for example:
```
$ ln -s ../../../../ps/audio-processing.c
```
Switch back to SDK/Eclipse and refresh the Project Explorer view.
Build the application with Project > Build All.
Once build completes, program your FPGA with audio_processing_wrapper.bit by means of Xilinx > Program FPGA.

The blue LED Done should light up.
Run the audio-processing project with Run > Run > Launch on Hardware (GDB).

You can see the whole system working in the uploaded video audio-processing.3gp.