This week, I worked with Jose and Misho to properly integrate all of our modules into a top-level design. By doing this, we were able to successfully output a sine wave playing at different frequencies, based on a simulated key press through the FPGA switches! The next steps on my end involve creating the ADSR envelope for the note amplitude. Once that’s done, I’ll talk with Misho about integrating it into his filter design. I also need to validate the note frequency (for now, we will hook up the FPGA to a speaker and then use a tuner app to validate the frequency of the outputted note) and integrate interpolation for the other waveforms (saw, square, triangle).
I have also started thinking about how to integrate the drum track into our design. Although the samples will be quite small in memory footprint, we want to support as many as possible. Thus, it may be necessary to use the SD card for extra memory and interface with the Arm core. The MVP for this should still be just using BRAM, but it’s possible that we can have a reach goal that involves using this more ambitious goal. Another question to consider is the input interface for the drums. I would love to have a nice, 3D printed design and chassis that we can interface with to give the user a more intuitive feel. However, we will see if we have enough time at the end of the project.
All in all, I am happy with the progress we have made and believe that we are on a good pace.