Week Six
This weeks assignments
- Design a hello world microcontroller board - modeling an existing file and adding a led and a pushbutton
- Design in PCB design software - Eagle
- Mill out design
- Solder parts to PCB
Practicals.
Eagle - PCB design software
Eagle has a very friendly user interface and smooth learning curve. It felt very intuitive after the first few minutes playing around with it. I have experimented with Fritzing before using eagle, so maybe I kind of knew what I was getting into when I started. To begin, we start with importing the Fablab library, which can be done here. The library is basically just downloaded to the workfile where the projects are stored. In my case it was in "my documents" under "eagle. After the library is downloaded, then a new project is started and all the libraries except the fablab one and one called supply1.
The schematic is opened, all the parts needed placed inside and then the nessecary channels connected.
Once all the parts are connected togeather, we generate the board so we can make the routs and organize the parts.
We place the parts neatly togeather, but just so that we can make routs that dont intersect. The original HelloWorld piece helped alot with organizing, even though organizing way differently would also be possible. The placement of the LED and the resistor worked such that if the button would be pressed, it would return a signal to the microchip, which in turn would also send a signal to the LED making it go on while the button were pressed. More on the in week 8.
Now off to play with the layers. In order to get millable PNG's we need to turn off all the layers except layer 1 (TOP), layer 20 (Dimensions) and a random layer make our work area bigger.I used layer 208, since thats what I was reccomended, but I assume other layers can be used just aswell.
Once both the traces and the outline PNG's have been produced, its of to milling. The outline image was worked in eagle in another computer - need to fix.
Mill out PCB and solder parts
Milling out PCB's is awesome. No question about it. Pretty straight forward since we've done this part before.
After milling all the pieces needed to be soldered onto the board. Classic messy work environment... I didint run into any specific problems soldering.
And board ready!
