7. Electronics design¶
Introduction¶
This week, we had two assignments, with one being a group assignment and one being an individual assignment. The group assignment for this week was to test equipment in our lab to observe the operation of a microcontroller circuit board. The individual assignment this week was to design/ redraw an echo board from scratch using a program like EAGLE or KiCad.
Group Assignment¶
This week, I decided to start with the group assignment, which was to test the equipment in our lab to observe the operation of a microcontroller circuit board. This week we worked in smaller groups so that we could all have time to truly understand what we were doing and what we were using. We used a mutlimeter and an oscilliscope to find certain values of the board. The link to the group page is here
Individual Assignment - designing the pcb¶
This week our individual assignment was to create a PCB from scratch that would be able to blink and echo. I first designed a board which I thought would be able to do both, but it ended up only doing the blink. Later in the week, I designed a board that would be able to do both things. For all of my designs, I used EAGLE, as Mr. Neil recommended people who like Fusion 360 to try EAGLE, and so I did. I first started off by watching some tutorials on EAGLE, which explained things such as schematics, parts, connections, routing, and setting the final board. The link to the first video is here and the link to the second video is here Once I felt that I got a hang of the program, I decided to replicate the board the Mr. Neil had put up on the Fab Academy website to see if I could get all the parts together and create a successful board. With this process, I was able to get all of the libraries that I needed, which I got off of the fab academy folder.
I created the ATTiny 412 version of the board, which is newer compared to the ATTiny 45. We were told that we should not worry about the specifics of the chips and the board YET, but I was able to obtain a lot of information about the board itself such as the pin outs and other connections, which I thought was good, breaking down electronics once piece at a time. Here is an image I used to learn about the chips ports were
After I did this, I started from scratch, and got all the components, and then I designed what I thought would be both a echo and blink board, but it turned out to be a blink board due to me not drawing a trace from the RXD to one of the pins on the chip. I first got all my components after searching for a while and placed them, which looked like this
After I got all of my pieces, I started my traces, which ended up looking like this.
Once I did this, I believed that I was ready to go, so I went under file and open as a board. Once I did this, It gave me all of the pieces in the board format, and I arraged them, which looks like this.
After I did that, I went to this website in order to get the DRC file I needed for the design rules. Once I got it downloaded, I got the 64th bit version of the file into my design rules folder under EAGLE in the documents of my computer, and I was able to get the proper rules in.
After this, I moved the pieces around a bit, then used the auto trace feature, set the last option to N/A, and set the effort to high, and let it run, and the end product looked like this.
After I was done with this, I shrunk the border around the board, and then saved it and went to the mill to get it cut out. Once the board was cut out, I got all of my components, which are in the picture below.
Once I collected all of these materials, I was able to get them soldered on, which ended up like this.
Programming the board¶
Once I completed soldering the board, I started with the programming of the board. This week, we were to test some code, which I got from the fab website that Mr. Neil provided us with, and I downloaded the code from the fab website, and then I opened the Arduino application. I opened a new file, pasted the code into the program, and then I changed the ports in order for me to be able to run the code. Here is the link to the blink code.
Once it completed uploading, I got the board to blink
Echo and Blink¶
Once I had completed this, I needed to create an echo board, so I started yet again from the drawing board. I opened up EAGLE, and I copied and pasted my blink board to the new file. Once I did this, I changed a few traces, and got the schematic to look like this
Then, I converted my file into a board, autoroutes, and then I ended up with a board file that looks like this.
Once I did this, I cut out my board, and I soldered on the same pieces, which ended up looking like this (photo taken during echo code upload :> )
Uploading Code p.2¶
Once I got my board designed, cut, and soldered, I went back to my computer, and I uploaded the blink code, which worked. The link to the blink code is here
Then, I finally tested my echo function, which ended up working like this
Summary¶
This week, I believe that I learned a lot, especially with making boards/ working with EAGLE. Although I thought that this week would be somewhat easier, with us only adding a button to a design, I really understood the importance of the little details with these boards, as even one connection can make the difference between a working board and a non-functional board. I learned a lot about designing electronics, and look forward to what I can do with these tiny mircrocontrollers!