For successful circuit-building exercises, follow these steps: You will learn much more by actually building and analyzing real circuits, letting your test equipment provide the “answers” instead of a book or another person. While this is good, there is a much better way. Typically, students practice by working through lots of sample problems and checking their answers against those provided by the textbook or the instructor. I think it lends a modern look.Learning to mathematically analyze circuits requires much study and practice. Rather than a cabinet or plexiglass display, I chose meters free-floating in a colorful box. There are many ways to display the finished project. You may focus on designing how to mount the meters in a creative way. The ease at which you can do this with Trinket allows you to build this type of clock quickly and compactly.

There are several projects on the web using analog meters to tell time. This circuit varies the pulse width sent to the meters proportional to the hour of the day and the minutes after the hour.įor two meters, we will use two of the three PWM pins on Trinket (the third is also an I2C pin connected to the clock module). For wide pulses, the meter sees nearly the supply voltage and will stay around the full scale. If you have narrow pulses, the average voltage it sees is lower, thus the current is lower for the fixed resistance attached to it. The meter uses a moving coil inductance movement, acting to average the indication of current flowing through it. Trinket has pulse width modulation (PWM) on three of its pins. The Trinket can output to a meter without digital to analog converters. But rather than use the traditional digital display, the display is done using two analog meters. This project interfaces Trinket to the the Adafruit DS1307 real-time clock (RTC) breakout board to form a clock. Adding a digital display via I2C is possible using seven segment or character-based displays (with the library code posted for other projects).

And clocks don't need a lot of logic, this example only has maybe 20 lines of code. Trinket lends itself very well to building clock projects, its small and easy to hide behind a larger display.

Adafruit trinket 5v clock tutorial