Vernier Shield Hookup Guide
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Vernier Sensor Identification
Vernier developed a very clever method to identify sensors connected to their interface using a simple, passive resistor. Many Vernier sensors can be uniquely identified by a specific resistor placed between the AutoIDENT pin and GND.
We have integrated a 10k Ohm pull-up resistor on the shield so that we can directly measure the AutoIDENT resistor using a simple voltage divider calculation.
Nominal Resistor and voltage values for Vernier sensors
We've collected a list of popular sensors used by Vernier and their corresponding unique IDENT resistor values. These are nominal values and may vary within +/- 5%.
Analog Sensors
Digital Sensors
You will notice that there are not 70 sensors listed here. For all new sensors, Vernier has standardized on an I2C interface to query and communicate SensorID and calibration data. An example of this code is explained in the next section.