NanoPI

Pinout

https://wiki.friendlyarm.com/wiki/index.php/NanoPi_NEO

GPIO Programming

Using this module: https://pypi.org/project/NPi.GPIO/

Example code (python2):

import NPi.GPIO as GPIO
import time
PIN_NUM = 3

GPIO.setmode(GPIO.BOARD)
GPIO.setup(PIN_NUM,GPIO.OUT)
while True:
        GPIO.output(PIN_NUM,True)
        time.sleep(1)
        GPIO.output(PIN_NUM,False)
        time.sleep(1)

CPU Frequency

link

Default values

cat /sys/devices/system/cpu/cpu0/cpufreq/scaling_governor

ondemand

cat /sys/devices/system/cpu/cpu0/cpufreq/scaling_setspeed

<unsupported>

cat /sys/devices/system/cpu/cpu0/cpufreq/scaling_available_frequencies

480000 648000 816000 960000 1008000 1104000 1200000 1296000 1368000

Set new value

echo userspace > /sys/devices/system/cpu/cpu0/cpufreq/scaling_governor
echo 800000 > /sys/devices/system/cpu/cpu0/cpufreq/scaling_setspeed

you can check current frequency

cat /sys/devices/system/cpu/cpu0/cpufreq/scaling_cur_freq

Commands

# debug GPIO
cat /sys/kernel/debug/gpio

# Read CPU Temperature
echo $((`cat /sys/class/thermal/thermal_zone0/temp` / 1000))

Preparing

git clone https://github.com/friendlyarm/WiringNP
cd WiringNP/
chmod 755 build
./build

check it works by gpio readall

Examples

ds18b20

git clone https://github.com/Jacajack/avr-ds18b20

Power Consumption

Temperature measurements were taken outdoors on a table. It was 23-24 degrees in the room.

At a frequency of 1368000 and 4 cores loaded at 100% - 0.5 Ampere, the temperature reaches 80 degrees (I didn’t torture it any further)

At a frequency of 480000 and 4 cores loaded at 100% - 0.27 Ampere, the temperature reaches 60 degrees and grows very slowly (I didn’t wait)