resource-monitor.ino

// include the library code:
#include <Wire.h>
#include <Adafruit_MCP23017.h>
#include <Adafruit_RGBLCDShield.h>

Adafruit_RGBLCDShield lcd = Adafruit_RGBLCDShield();

// These #defines make it easy to set the backlight color
#define RED 0x1
#define YELLOW 0x3
#define GREEN 0x2
#define TEAL 0x6
#define BLUE 0x4
#define VIOLET 0x5
#define WHITE 0x7

void setup() {
  Serial.begin(9600);
  lcd.begin(16, 2);
  lcd.setBacklight(TEAL);
  lcd.clear();
}

uint8_t i=0;
void loop() {
  // Backlight control
  uint8_t buttons = lcd.readButtons();
  if (buttons) {
    if (buttons & BUTTON_UP) {
      lcd.setBacklight(RED);
    }
    if (buttons & BUTTON_DOWN) {
      lcd.setBacklight(YELLOW);
    }
    if (buttons & BUTTON_LEFT) {
      lcd.setBacklight(GREEN);
    }
    if (buttons & BUTTON_RIGHT) {
      lcd.setBacklight(BLUE);
    }
    if (buttons & BUTTON_SELECT) {
      lcd.setBacklight(VIOLET);
    }
  }
  
  // Show stuff:
  if(Serial.available() > 0) {
    String input = Serial.readStringUntil('\n');
    int firstCommaIndex = input.indexOf(',');
    int secondCommaIndex = input.indexOf(',', firstCommaIndex+1);
    int thirdCommaIndex = input.indexOf(',', secondCommaIndex+1);
 
    String cpu = input.substring(0, firstCommaIndex);
    String ram = input.substring(firstCommaIndex+1, secondCommaIndex);
    String down = input.substring(secondCommaIndex+1, thirdCommaIndex);
    String temp = input.substring(thirdCommaIndex+1, thirdCommaIndex+5);

    Serial.flush()

    /*
    Serial.println(cpu);
    Serial.println(ram);
    Serial.println(down);
    Serial.println(up);
    Serial.println();
    */
    
    lcd.clear();
    // CPU:
    lcd.setCursor(0,0);
    lcd.print(cpu);
    lcd.print("%");
    // RAM
    lcd.setCursor(9,0);
    lcd.print(ram);
    lcd.print("MB");
    
    // Download
    lcd.setCursor(0,1);
    lcd.print(down);
    lcd.print("k");

    // Temp
    lcd.setCursor(9,1);
    lcd.print(temp);
    lcd.print("C");
  }
}

resource-monitor.py

#!/usr/bin/python

import psutil
import serial
import time
import datetime
import sensors

from serial import SerialException


init = False
ser = None

def write():
    global init, ser
    try:
        if not init:
            # connect to the Arduino if necessary
            try:
                ser = serial.Serial('/dev/ttyACM0', 9600, timeout=1)
            except SerialException:
                ser = serial.Serial('/dev/ttyACM1', 9600, timeout=1)
            init = True
        # write data to the Arduino
        _data = [str(DATA['cpu']), str(DATA['ram']), str(DATA['down']), str(DATA['temp'])]
        # print _data
        if ser:
            ser.write(",".join(_data))
    except SerialException:
        if ser:
            ser.close()
        init = False # reinitialise in the next loop
        pass


def get_temp():
    sensors.init()
    try:
        for chip in sensors.iter_detected_chips():
            for feature in chip:
                if feature.label.startswith("Physical"):
                    return feature.get_value()
    finally:
        sensors.cleanup()


DATA = None
poll_time = 0 # time of last poll
last_recv = 0
last_sent = 0

def poll_resources():
    global DATA, poll_time, last_recv, last_sent

    now = datetime.datetime.now()
    cpu_percent = psutil.cpu_percent()
    ram_avail = psutil.phymem_usage().available/(1024*1024)
    net_io_counters = psutil.network_io_counters()

    # calculate time
    new_poll_time = (now.day * 24 * 60 * 60 + now.second) * 1000 + now.microsecond / 1000.0
    diff_time = (new_poll_time - poll_time)/1000.0 # seconds diff
    poll_time = new_poll_time

    # calculate download rate
    down = (net_io_counters.bytes_recv-last_recv)/(1024.0*diff_time)
    down = 0.0 if down <= 0.0 else round(down,1)

    # Temperature
    temp = get_temp()

    # remember state
    last_recv = net_io_counters.bytes_recv
    last_sent = net_io_counters.bytes_sent
    DATA = dict(cpu=cpu_percent, ram=ram_avail, down=down, temp=temp, poll_time=poll_time)


if __name__ == '__main__':
    # init data
    while True:
        # gather data (resource usage)
        poll_resources()
        write()
        time.sleep(2)

win-resource-monitor.py

#!/usr/bin/python

import psutil
import serial
import time
import datetime

from serial import SerialException


init = False
ser = None

def write():
    global init, ser
    try:
        if not init:
            # connect to the Arduino if necessary
            ser = serial.Serial('COM4', 9600, timeout=1)
            init = True
        # write data to the Arduino
        _data = [str(DATA['cpu']), str(DATA['ram']), str(DATA['down']), str(DATA['temp'])]
        # print _data
        if ser:
            ser.write(",".join(_data).encode())
    except SerialException:
        if ser:
            ser.close()
        init = False # reinitialise in the next loop
        pass


def get_temp():
    return "--"


DATA = None
poll_time = 0 # time of last poll
last_recv = 0
last_sent = 0

def poll_resources():
    global DATA, poll_time, last_recv, last_sent

    now = datetime.datetime.now()
    cpu_percent = psutil.cpu_percent()
    ram_avail = psutil.phymem_usage().available/(1024*1024)
    net_io_counters = psutil.network_io_counters()

    # calculate time
    new_poll_time = (now.day * 24 * 60 * 60 + now.second) * 1000 + now.microsecond / 1000.0
    diff_time = (new_poll_time - poll_time)/1000.0 # seconds diff
    poll_time = new_poll_time

    # calculate download rate
    down = (net_io_counters.bytes_recv-last_recv)/(1024.0*diff_time)
    down = 0.0 if down <= 0.0 else round(down,1)

    # Temperature
    temp = get_temp()

    # remember state
    last_recv = net_io_counters.bytes_recv
    last_sent = net_io_counters.bytes_sent
    DATA = dict(cpu=cpu_percent, ram=ram_avail, down=down, temp=temp, poll_time=poll_time)


if __name__ == '__main__':
    # init data
    while True:
        # gather data (resource usage)
        poll_resources()
        write()
        time.sleep(2)