readVoltage

Read voltage from analog input pin

Syntax

voltage = readVoltage(bbb, pin_name)

Description

voltage = readVoltage(bbb, pin_name) measures the voltage applied to an analog input pin relative to the ADC ground pin (GND_ADC).

The BeagleBone Black board has six analog input pins. Each analog input pin has a 12-bit ADC that converts the analog input voltage to a digital voltage reading. The ADC-driver built into the Linux^® kernel returns the voltage measurement converted to a double. The values range from 0 V (GND_ADC) to 1.8 V (VDD_ADC).

Caution

• Never connect a voltage greater than 1.8 Vacross the ADC pins. Voltages greater than 1.8 V can damage the board.

• Always connect the negative (ground) side of a voltage source to GND_ADC. The ADC measures positive voltages only. A reversed connection can damage the board.

Examples

Read Voltage at Pin

Read voltage at pin 'AIN0'

bbb = beaglebone();
readVoltage(bbb, 'AIN0')

ans = 

1.64

Input Arguments

bbb — Connection to BeagleBone^® Black hardware

beaglebone object

BeagleBone Black connection created using beaglebone, specified as an object.

pin_name — Name for analog input

character vector

Name character vector.

Example: 'AIN0'

Data Types: char

Output Arguments

voltage — Voltage at analog pin, in volts

double

Voltage at analog GPIO pin, in volts

Version History

Introduced in R2015a