Category: An Arduino Ohmmeter

The operation of the Arduino Ohmmeter is based around the concept of the voltage divider. Two resistors are connected in series, and the reading is taken from where the two resistors join. The voltage measured at that point is the ratio of R2/(R1+R2) multiplied by the voltage in. For example, if R2 is 10K and R1 is…

It’s time to upload the Ohmmeter sketch to the Arduino. Example 13-1 reads the resistance of R2, and reports the result through the serial display. Here are the steps you’ll need to take: Once the Ohmmeter sketch has been uploaded to the Arduino, place the unknown resistor (shown as R2 on the Frizting diagram) you want to test…

This gadget tests the resistance of electrical components. Place the unknown resistor you want to test in series with the reference resistor R1 connected to GND. The Arduino will calculate the resistance and display it on the Serial Monitor. The resistance of other electrical objects can be measured with the Arduino Ohmmeter as well. Building the…

Figure 13-1. An Arduino Ohmmeter

Resistors are color coded to indicate their resistive value. If you already know how to read the color code—or once you learn how—you’ll be able to glance at a resistor and tell automatically what its value is. But what about other components in your projects? What about the LEDs, potentiometers, buzzers, or even the wires…