Overview Link to heading

For this week I decided to experiment with ways to increase my effective pin number. I decided to have two ATtinys connected to a XIAO with each ATtiny connected to a bunch of buttons. The reasoning behind this configuration was that I would be able to use ATtinys to create tiny hubs of buttons for my final project in order to compress wiring. I also opted for a simple design that would join the inputs and output of the ATtinys, this would allow me to broadcast messages easily and also easily develop a communication algorithm.

Initial design Link to heading

Circuit design

Circuit design

One of the significant features of the design is the integrated converter near each of the Attinys used for programming. Turns out that this is quite a well known problem that has been faced by previous students. Fortunately, there exists this great resource that guides one through how to make such a converter.

Manufacturing Link to heading

While trying to add the pins to their proper places I accidentally ripped one of the copper pads of the board rendering it unusable. This issue was most likely partially caused by accidentally heating the copper beneath the pad for too long.(One can observe the effect on the right side of the image)

Broken board

Broken board

The back-up plan Link to heading

Due to physical boards being prone to breaking and causing great frustration, I decided to pivot towards a wireless network. Fortunately, this would both allign with my final project goals and would be implemented quite easily. Even more fortunately, the lab had a great supply of Raspberry Pi Pico W’s that I could use for testing. One can see a more complete example of this on the final project page itself, but in short there are many great api’s that one can integrate into a project.

As an additional bonus, turns out that the SPI connection between the raspberry pi and the display counts as a network connection.

Here is a snippet of what the use of an api for cat images and an api of cat facts can create:

Snippet

Snippet