Engineering to Design: SimonSays [PART 2]
The first batch of PCB boards came in for the SimonSays project and they look great. I found some trivial errors after I sent them out and made a revision to the layout files. I drew up the schematic with the wrong transistor so the emitter and collector are backwards and there was a redundant resistor pulling reset high.
Here’s how they looked before I started adding components:
I used the DorkBotPDX PCB service and am very happy with the manufacturer that they use. You can’t see it in the pictures but the purple solder mask and gold plated contacts look excellent. I didn’t have all the components ready to put one together last night, so I desoldered the prototype and built one from those parts. Everything works great besides the transistor for the buzzer is incorrect and i’m having a slight reset issue that is easily fixed by a capacitor.
The easy part of this project is done. Now it’s time to write up the whole process in a format that is conducive to teaching a class on the subject of embedded design. This is meant for a beginner/intermediate course for students that have a very basic understanding of electronics and programming to get started with micro-controllers. Part 3 of this write up will include the finalized course PDF, layout files, and source code. The class won’t follow the step by step process of creating the SimonSays game, but use it as an example platform to convey ideas and solutions.