< and the [USB footprint](https://gitlab.cba.mit.edu/classes/863.21/site/-/issues/29) that Zach posted.
After importing the library, I took inspiration from a lot of different boards ([echo hello](http://academy.cba.mit.edu/classes/embedded_programming/D11C/hello.D11C.echo.1.png) and [blink](http://academy.cba.mit.edu/classes/embedded_programming/D11C/hello.D11C.blink.png)). I went with the same SAM D11 C-14 chip that we used last time, since I don't have that much experience with microcontrollers and the section TFs said that was the simplest to use. The button and LED were all given to us, and I used the same 2x2 connector from our week 3 echo board. A lot of the other components were pulled directly from that board as well, with resistor and capacitor values pulled from the [KiCad](https://vimeo.com/625848785/cbcd8b5d3e) and [Eagle](http://mtm.cba.mit.edu/2021/2021-10_htmaa-demo/) recitations. Rob was also a big help here, to help me figure out what resistors/capacitors I actually needed.
Once I laid out all of the symbols on my schematic (pressing a to add in the symbols before looking them up in the fab library), I had to actually wire them up. To do this, I followed the above mentioned boards. I wired up the voltage regular, capacitor, resistors, USB power source, and 2x2 connector like it was done in hello echo. To add in the button and LED, I just looked at the SAM D11 data sheet to figure out which pins I could use. It turned out that I could use most of the pins, so I just chose two random ones to wire up the button and LED. Per Rob's advice, I wired the button to a spearate pin from the LED. Thus, I could use my code to detect when a specific button got pressed, to then trigger the LED turning on and off. Then, I was left with the below schematic. I didn't have the libraries downloaded (somehow my KiCad library paths were not linked properly), so I used a 1x4 symbol for the USB.
<figure><img src="../images/full/05/schema_pt1.png" width="500"/>
</figure>
Once I had my schema, that's when I ran into a large problem. For some reason, my KiCad was not letting me open up the PCB editor to actually set up the traces and footprints. When I opened it up, there was no black screen + I was unable to load in my netlink file. That's when I talked to Reuben and I realized I was also missing the builtin libraries. I thought this was an issue where I didn't download the Library Support folder, so I redownloaded KiCad. However, even after waiting to download both the application and the support files, my KiCad still didn't work.
<figure><img src="../images/full/05/no_pcb.png" width="500"/>
</figure>
After fumbling around in KiCad and redownloading it multiple times with no success, Reuben kindly let me use his laptop (with a working KiCad program) to create my schematic and traces. He also had the built in libraries installed, so I was able to add in the actual USB connector. After a lot of routing and re-routing to fit things together, I was able to come up with a successful svg file:
schematic | traces |
:---------------:|:---------------:
 | 
## Creating the SVG Files
Now that I had the actual SVG files, I had to split the file apart into the copper trace cuts and the outline cut. I downloaded InkScape to do so, but had a lot of trouble with it. I was able to create the cu and outline layers easly, as described in the KiCad recitation. However, I was unable to join the polygon for the outline and fill it in as described. After combining/joining/uncombining/recombining the outline in many different iterations, I was still unable to fill the outline in using fill and stroke. When I manually used the paint bucket option, my fill had some white lines/patches in it:
<figure><img src="../images/full/05/broke_outline.png" width="500"/>
</figure>
Finally, I somehow fiddled around enough + selected/joined things in the right order, and was able to use the paint bucket option to get a weird semblance of an outline. It was not exactly the shape I had originally imported (it had slightly bevelled corners), but I wasn't complaining at this point. The outline didn't cut into my traces anywhere, so I called it a day and exported the two layers as separate plain SVG files.
final outline | final traces |
:---------------:|:---------------:
 | 
## Milling and Soldering
I was feeling pretty good about milling and soldering, since we had done it already. However, I ran into a few issues. The first time I tried milling it out, I didn't put enough tape on the backside and the plate moved with the bit. Ater cancelling that, I also realized that I was cutting inside the traces, rather than cutting them out. After inverting it and fully securing the plate, I was able to mill out the traces.
<figure><img src="../images/full/05/milled_traces.png" width="500"/>
</figure>
At first, I thought it was way too small. The pads looked pretty small, and the traces were all super tiny (compared to what I remembered from week 3). However, after looking at it a bit more and putting the actual components on the board, I realized it was the right size fit. Then, I swapped out the bit and milled out the outline. Finally, I was ready to solder!
<figure><img src="../images/full/05/milled_part.png" width="500"/>
</figure>
Once my part was milled (and the size was confirmed to be correct), I went to solder. At first, I had a tough time soldering. I soon realized it was becuase I was using lead-free solder, which Nathan had said was harder to solder with than normal solder. This lead to some connections that had this werid frosty/white texture to it (circled red in the photo below). After switching to normal solder, I was able to continue like normal. It was still harder than last time -- last time, the pads were a little larger and easier to solder on. But, I was able to get everything on the board!
<figure><img src="../images/full/05/final.png" width="500"/>
</figure>
]]>