This week was proposal presentation week! We got to see some cool projects, many of which are audio or signal processing related. We received positive feedback from other groups!
This week I finished up the UI trade, outlining our user interface module’s requirements and looking at different options for components. This required research into different kinds of displays (such as TFT LCD pros and cons), and I learned about how LCD screens work in the process. One constraint we had is being able to power it using a 3.3V supply, which limited our options. From there, I prioritized cost effectiveness and size. We want to make sure the UI is easy to navigate and able to enable a user to quickly adjust parameters. I also selected a rotary encoder with a button, but we ultimately ended up getting a new model of the same one for cheaper!
I also worked on the interface between the UI module and the microcontroller. I got my hands dirty looking at the LCD screen’s data sheet and also how utilize the FMSC feature of the microprocessor in order to efficiently connect the LCD. I did some research on the pinout for the rotary encoder and switch, and found some GPIO pins to connect it to. Finally, I researched different footswitches, since we want to include a toggle switch for quick effect-toggling during a performance. I learned about single, double, and triple pole switches and also single, double, and triple throw switches. While a TPDT switch is standard for a lot of guitar pedals, we can have the microcontroller process the toggle, so we really only need a SPST switch. The other thing I looked for was a clicky/tactile feel when you toggle the switch since I know I personally like that feedback when I am using an effects processor.
I also worked with Adam and Xingran to finalize a budget for our project, selecting our components.
I looked into implementing digital effects, and have started a game plan for each (EQ, reverb, chorus). Next week I will begin to write some MATLAB code to actually test my architected designs. I’ll use the sample guitar input I provided Adam to test the analog effect and hear how the effects shape the output. The UI to microcontroller interface took longer than expected, so I did not work on this as much as I had hoped this week. Progress should be a lot better now that I can focus on it this week!