'ODROID-N2' on this page refers to the ODROID-N2 series (N2, N2+, N2L).
ADC
There are 2 ADC input ports on the 40-pin header.
| Pin #37 | Pin #40 | |
|---|---|---|
| ODROID-C2 | ADC.AIN1 | ADC.AIN0 |
| ODROID-C4 | ADC.AIN2 | ADC.AIN0 |
| ODROID-N2 | ADC.AIN3 | ADC.AIN2 |
| ODROID-M1/M1S | ADC.AIN1 | ADC.AIN0 |
You can access the ADC inputs via sysfs nodes.
| Pin #37 | Pin #40 | |
|---|---|---|
| ODROID-C2 | /sys/class/saradc/ch1 | /sys/class/saradc/ch0 |
| ODROID-C4 | /sys/bus/platform/drivers/meson-saradc/ff809000.saradc/iio:device0/in_voltage2_raw | /sys/bus/platform/drivers/meson-saradc/ff809000.saradc/iio:device0/in_voltage0_raw |
| ODROID-N2 | /sys/bus/platform/drivers/meson-saradc/ff809000.saradc/iio:device0/in_voltage3_raw | /sys/bus/platform/drivers/meson-saradc/ff809000.saradc/iio:device0/in_voltage2_raw |
| ODROID-M1 | /sys/bus/platform/drivers/rockchip-saradc/fe720000.saradc/iio:device0/in_voltage7 | /sys/bus/platform/drivers/rockchip-saradc/fe720000.saradc/iio:device0/in_voltage6 |
| ODROID-M1S | /sys/bus/platform/drivers/rockchip-saradc/fe720000.saradc/iio:device0/in_voltage3 | /sys/bus/platform/drivers/rockchip-saradc/fe720000.saradc/iio:device0/in_voltage2 |
ADC's maximum sample rate is 50kSPS. ODROID-C2/M1/M1S has 10bit resolution (0~1023). ODROID-C4/N2 has 12bit resolution (0~4095).
But the actual sample rate is 8kSPS if you access it via sysfs due to the limited file IO speed.
The ADC inputs are limited to 1.8Volt. If the input voltage is higher than 1.8Volt, you will fry your ODROID board.
This WiringPi example code shows how to access the ADC for C/C++ programming.
Introduction C Tinkering Kit on Ubuntu
Library Source code WiringPi port for ODROID-C0/C1/C2/XU3/XU4
luke.go