13-04-2016, 08:04 AM
Building the digital tachometer came out successfully as we saw in the data & observations section. The video showed the circuit with a computer fan interrupting the emitter/detector circuit which sent rising edge signals of +5v to the microcontroller. The LCD output the proper value from the rpm counter corresponding to the fan's current speed and it was accurate! One additional thing I did do to verify, was capture the pulse frequency on an oscilloscope and make sure it matched up with the LCD's RPM data which it did.