Example programs for the SDS-011

plot.py

import serial
import struct
from collections import deque
import numpy as np
import matplotlib.pyplot as plt
import matplotlib.animation as anim
from matplotlib.ticker import FuncFormatter

# Change this to the right port - /dev/tty* on Linux and Mac and COM* on Windows
PORT = 'COM5'
MAX_LENGTH = 60
UNPACK_PAT = '<ccHHHcc'

pm25_history = deque(np.zeros(MAX_LENGTH), maxlen=MAX_LENGTH)
pm10_history = deque(np.zeros(MAX_LENGTH), maxlen=MAX_LENGTH)

x = np.arange(0, MAX_LENGTH)

fig, ax = plt.subplots()
ax.set_ylim(0, 15)
ax.set_xlim(0, MAX_LENGTH - 1)
line_pm25, = ax.plot(x, np.zeros(MAX_LENGTH), color='r')
line_pm10, = ax.plot(x, np.zeros(MAX_LENGTH), color='b')
ax.xaxis.set_major_formatter(FuncFormatter(lambda x, pos: '{:.0f}s'.format(MAX_LENGTH - x - 1)))
plt.title('PM2.5/PM10')

ser = serial.Serial(PORT, 9600, bytesize=8, parity='N', stopbits=1)

def init():
    return line_pm25, line_pm10

def animate(i):
    packet = ser.read(10)
    unpacked = struct.unpack(UNPACK_PAT, packet)
    pm25 = unpacked[2] / 10.0
    pm10 = unpacked[3] / 10.0
    pm25_history.append(pm25)
    pm10_history.append(pm10)
    line_pm25.set_ydata(pm25_history)
    line_pm10.set_ydata(pm10_history)
    return line_pm25, line_pm10

animation = anim.FuncAnimation(fig, animate, init_func=init, interval=1000, blit=True)

plt.show()

simple.py

import serial
import struct
from datetime import datetime

# Change this to the right port - /dev/tty* on Linux and Mac and COM* on Windows
PORT = 'COM5'

UNPACK_PAT = '<ccHHHcc'

with serial.Serial(PORT, 9600, bytesize=8, parity='N', stopbits=1) as ser:
    while True:
        data = ser.read(10)
        unpacked = struct.unpack(UNPACK_PAT, data)
        ts = datetime.now()
        pm25 = unpacked[2] / 10.0
        pm10 = unpacked[3] / 10.0
        print("{}: PM 2.5 = {}, PM 10 = {}".format(ts, pm25, pm10))