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Week 11: Networking

For this week's output assignment, I wanted to design, stuff, program and test a board that includes Bluetooth/Wifi, a color LED, and accelerometer that I could use as a starting point for my final project — programmable smart juggling balls.

Designing the Board

I based this week's board off of week 10's accelerometer board.

A few interesting EAGLE things I learned:

  • You should create an outline on a random layer (e.g. Notes) to force the exporting script to have some margin around the edges
  • Photoshop couldn't see a 1px line at the bottom of the exported images! Some sort of issue with importing?
  • You can flip layer visibility on and off using EAGLE's console (thanks Joao!)

I exported the board to PNGs:

python eagle_png.py RGB-Accel.brd

This generated .top.png and .cutout.png files. These had 3000 DPI as before, so I resized them in Photoshop to 50%.

One interesting thing to note — when I would export them using imgur, imgur would strip the DPI from the PNG metadata, resulting in mods loading it as 32dpi

My board top took a super long time to calculate and recalculate in mods (~1-2 minutes, barely responsive computer). Possibly because my board layout was large, or some artifact of how I exported it.

The library's default pads for the ADXL was too large for our design rules, and Jake Read showed me how to edit board footprints, which was easier than I thought.

I mixed up the wire and route commands initially, thinking something was wrong with my board components or board GUI. Eventually I realized the mistake.

Some pads had tiny extra airwires that would count as unconnected. I wasn't able to sort out.

The ESP32 from the library I had also had a mounting.

I wasn't able to figure out how to get the holes from the toggle switch to export properly.

Milling the Board

The milling was straightforward!

  1. I made sure the part of the board I was milling on was stable by pushing down on it with a paper towel. One side of the sacrificial layer had bounce to it, but I milled on the opposite side and it worked OK.