Using the AD Converter of the 60 Series SOM DVK Requirements 60-SOM DVK, Power Supply, microUSB cable PC with terminal program for accessing the console of the 60-SOM DVK Lab power supply to insert voltages and multimeter to verify voltage reading Setting up Start by creating a fresh SD card to boot your 60-SOM DVK as described in the 60-SOM Getting Started guide Download the latest release from the 60-SOM releases page on Github: When done, insert the freshly written SD card into your 60-SOM DVK and boot: The default username is “root”, and the default password is “summit”. Summit Linux som60sd-laird-7.648.0.13 summit login: root Password: # Reading the ADC Query the ADC capabilities of the 60-SOM DVK with the following command: grep -H "" /sys/bus/iio/devices/*/name | grep adc Reply: # grep -H "" /sys/bus/iio/devices/*/name | grep adc /sys/bus/iio/devices/iio:device0/name:f8018000.adc /sys/bus/iio/devices/trigger0/name:f8018000.adc-dev0-external-rising /sys/bus/iio/devices/trigger1/name:f8018000.adc-dev0-external-falling /sys/bus/iio/devices/trigger2/name:f8018000.adc-dev0-external-any /sys/bus/iio/devices/trigger3/name:f8018000.adc-dev0-continuous As you can see in the reply, there is the ADC “device0”. Change to the directory for that device and issue the ‘ls’ command: cd /sys/bus/iio/devices/iio:device0/ # pwd /sys/bus/iio/devices/iio:device0 # ls buffer in_voltage3_raw name current_timestamp_clock in_voltage4_raw of_node dev in_voltage5_raw power in_voltage0_raw in_voltage6_raw scan_elements in_voltage10_raw in_voltage7_raw subsystem in_voltage11_raw in_voltage8_raw trigger in_voltage1_raw in_voltage9_raw uevent in_voltage2_raw in_voltage_scale # With referencing the below schematic snippet of the 60-SOM you can see that the following ADC pins are presented at J19 of the DVK: First read-out Place a jumper between pin1 and pin2 of J19. This shortens AD2 to GND and the readout should be 0: Issue the following command: cat in_voltage2_raw and you will see the confirmation that the voltage is zero. cat-in-voltage2-raw Other example readout: Interpreting the reading This reading reflects a 12bit ADC. You can verify this in the SAMA5D36 data sheet, available on the SAMAD536 product page at microchip.com. This is expressed as a decimal in the range of [0 to 4095]. An ADC reading as above of 2491 at a reference voltage of 3.3V (ADVREF) gives us: 3.3V x 2491 / 4095 = 2.01V Very near to the expected 2V. Warning: Never exceed the max voltage (3.3V) allowed for the ADC pins! If in doubt, consult the 60 Series SOM datasheet.