Introduction

This is a detailed project documentation for one of the videos we published on youtube. This is about making an IOT plant watering system using raspbery pi pico w

Components required

1) Raspberry Pi Pico W board

2) Relay

3)Usb Cable for program downloading

4) DC Power supply 5v and 12v

5)Water pump 5v

6) Plastic pipe for water distribution

7) Jumper wires

8) Breadboard

9)Small plastic jar for water storage

Circuit diagram for IOT Plant watering system using Rapsberry pi pico W

IOT Plant watering Circuit

Python Program for IOT Plant watering system using raspberry pi pico w

This is the BlynkLib.py, this is library code, use it as is without any changes/modifications

__version__ = "1.0.0"
 
import struct
import time
import sys
import os
 
try:
    import machine
    gettime = lambda: time.ticks_ms()
    SOCK_TIMEOUT = 0
except ImportError:
    const = lambda x: x
    gettime = lambda: int(time.time() * 1000)
    SOCK_TIMEOUT = 0.05
 
def dummy(*args):
    pass
 
MSG_RSP = const(0)
MSG_LOGIN = const(2)
MSG_PING  = const(6)
 
MSG_TWEET = const(12)
MSG_NOTIFY = const(14)
MSG_BRIDGE = const(15)
MSG_HW_SYNC = const(16)
MSG_INTERNAL = const(17)
MSG_PROPERTY = const(19)
MSG_HW = const(20)
MSG_HW_LOGIN = const(29)
MSG_EVENT_LOG = const(64)
 
MSG_REDIRECT  = const(41)  # TODO: not implemented
MSG_DBG_PRINT  = const(55) # TODO: not implemented
 
STA_SUCCESS = const(200)
STA_INVALID_TOKEN = const(9)
 
DISCONNECTED = const(0)
CONNECTING = const(1)
CONNECTED = const(2)
 
print("""
    ___  __          __
   / _ )/ /_ _____  / /__
  / _  / / // / _ \\/  '_/
 /____/_/\\_, /_//_/_/\\_\\
        /___/ for Python v""" + __version__ + " (" + sys.platform + ")\n")
 
class EventEmitter:
    def __init__(self):
        self._cbks = {}
 
    def on(self, evt, f=None):
        if f:
            self._cbks[evt] = f
        else:
            def D(f):
                self._cbks[evt] = f
                return f
            return D
 
    def emit(self, evt, *a, **kv):
        if evt in self._cbks:
            self._cbks[evt](*a, **kv)
 
 
class BlynkProtocol(EventEmitter):
    def __init__(self, auth, tmpl_id=None, fw_ver=None, heartbeat=50, buffin=1024, log=None):
        EventEmitter.__init__(self)
        self.heartbeat = heartbeat*1000
        self.buffin = buffin
        self.log = log or dummy
        self.auth = auth
        self.tmpl_id = tmpl_id
        self.fw_ver = fw_ver
        self.state = DISCONNECTED
        self.connect()
 
    def virtual_write(self, pin, *val):
        self._send(MSG_HW, 'vw', pin, *val)
 
    def send_internal(self, pin, *val):
        self._send(MSG_INTERNAL,  pin, *val)
 
    def set_property(self, pin, prop, *val):
        self._send(MSG_PROPERTY, pin, prop, *val)
 
    def sync_virtual(self, *pins):
        self._send(MSG_HW_SYNC, 'vr', *pins)
 
    def log_event(self, *val):
        self._send(MSG_EVENT_LOG, *val)
 
    def _send(self, cmd, *args, **kwargs):
        if 'id' in kwargs:
            id = kwargs.get('id')
        else:
            id = self.msg_id
            self.msg_id += 1
            if self.msg_id > 0xFFFF:
                self.msg_id = 1
                
        if cmd == MSG_RSP:
            data = b''
            dlen = args[0]
        else:
            data = ('\0'.join(map(str, args))).encode('utf8')
            dlen = len(data)
        
        self.log('<', cmd, id, '|', *args)
        msg = struct.pack("!BHH", cmd, id, dlen) + data
        self.lastSend = gettime()
        self._write(msg)
 
    def connect(self):
        if self.state != DISCONNECTED: return
        self.msg_id = 1
        (self.lastRecv, self.lastSend, self.lastPing) = (gettime(), 0, 0)
        self.bin = b""
        self.state = CONNECTING
        self._send(MSG_HW_LOGIN, self.auth)
 
    def disconnect(self):
        if self.state == DISCONNECTED: return
        self.bin = b""
        self.state = DISCONNECTED
        self.emit('disconnected')
 
    def process(self, data=None):
        if not (self.state == CONNECTING or self.state == CONNECTED): return
        now = gettime()
        if now - self.lastRecv > self.heartbeat+(self.heartbeat//2):
            return self.disconnect()
        if (now - self.lastPing > self.heartbeat//10 and
            (now - self.lastSend > self.heartbeat or
             now - self.lastRecv > self.heartbeat)):
            self._send(MSG_PING)
            self.lastPing = now
        
        if data != None and len(data):
            self.bin += data
 
        while True:
            if len(self.bin) < 5:
                break
 
            cmd, i, dlen = struct.unpack("!BHH", self.bin[:5])
            if i == 0: return self.disconnect()
                      
            self.lastRecv = now
            if cmd == MSG_RSP:
                self.bin = self.bin[5:]
 
                self.log('>', cmd, i, '|', dlen)
                if self.state == CONNECTING and i == 1:
                    if dlen == STA_SUCCESS:
                        self.state = CONNECTED
                        dt = now - self.lastSend
                        info = ['ver', __version__, 'h-beat', self.heartbeat//1000, 'buff-in', self.buffin, 'dev', sys.platform+'-py']
                        if self.tmpl_id:
                            info.extend(['tmpl', self.tmpl_id])
                            info.extend(['fw-type', self.tmpl_id])
                        if self.fw_ver:
                            info.extend(['fw', self.fw_ver])
                        self._send(MSG_INTERNAL, *info)
                        try:
                            self.emit('connected', ping=dt)
                        except TypeError:
                            self.emit('connected')
                    else:
                        if dlen == STA_INVALID_TOKEN:
                            self.emit("invalid_auth")
                            print("Invalid auth token")
                        return self.disconnect()
            else:
                if dlen >= self.buffin:
                    print("Cmd too big: ", dlen)
                    return self.disconnect()
 
                if len(self.bin) < 5+dlen:
                    break
 
                data = self.bin[5:5+dlen]
                self.bin = self.bin[5+dlen:]
 
                args = list(map(lambda x: x.decode('utf8'), data.split(b'\0')))
 
                self.log('>', cmd, i, '|', ','.join(args))
                if cmd == MSG_PING:
                    self._send(MSG_RSP, STA_SUCCESS, id=i)
                elif cmd == MSG_HW or cmd == MSG_BRIDGE:
                    if args[0] == 'vw':
                        self.emit("V"+args[1], args[2:])
                        self.emit("V*", args[1], args[2:])
                elif cmd == MSG_INTERNAL:
                    self.emit("internal:"+args[0], args[1:])
                elif cmd == MSG_REDIRECT:
                    self.emit("redirect", args[0], int(args[1]))
                else:
                    print("Unexpected command: ", cmd)
                    return self.disconnect()
 
import socket
 
class Blynk(BlynkProtocol):
    def __init__(self, auth, **kwargs):
        self.insecure = kwargs.pop('insecure', False)
        self.server = kwargs.pop('server', 'blynk.cloud')
        self.port = kwargs.pop('port', 80 if self.insecure else 443)
        BlynkProtocol.__init__(self, auth, **kwargs)
        self.on('redirect', self.redirect)
 
    def redirect(self, server, port):
        self.server = server
        self.port = port
        self.disconnect()
        self.connect()
 
    def connect(self):
        print('Connecting to %s:%d...' % (self.server, self.port))
        s = socket.socket()
        s.connect(socket.getaddrinfo(self.server, self.port)[0][-1])
        try:
            s.setsockopt(socket.IPPROTO_TCP, socket.TCP_NODELAY, 1)
        except:
            pass
        if self.insecure:
            self.conn = s
        else:
            try:
                import ussl
                ssl_context = ussl
            except ImportError:
                import ssl
                ssl_context = ssl.create_default_context()
            self.conn = ssl_context.wrap_socket(s, server_hostname=self.server)
        try:
            self.conn.settimeout(SOCK_TIMEOUT)
        except:
            s.settimeout(SOCK_TIMEOUT)
        BlynkProtocol.connect(self)
 
    def _write(self, data):
        #print('<', data)
        self.conn.write(data)
        # TODO: handle disconnect
 
    def run(self):
        data = b''
        try:
            data = self.conn.read(self.buffin)
            #print('>', data)
        except KeyboardInterrupt:
            raise
        except socket.timeout:
            # No data received, call process to send ping messages when needed
            pass
        except: # TODO: handle disconnect
            return
        self.process(data)

Below is the main code for running the project. You can modify it according to your needs about pins usage

import time
import network
from machine import Pin
import BlynkLib
 
wlan = network.WLAN(network.STA_IF)
wlan.active(True)
wlan.connect("Robotics Lab","Robotics@321")
 
BLYNK_AUTH = 'ozDgrBQOhQv0Hc-8z2oNHSIdscNyEHd6'
 
# Wait for network connection
wait = 10
while wait > 0:
    if wlan.status() < 0 or wlan.status() >= 3:
        break
    wait -= 1
    print('waiting for connection...')
    time.sleep(1)
 
# Handle connection error
if wlan.status() != 3:
    raise RuntimeError('network connection failed')
else:
    print('connected')
    ip = wlan.ifconfig()[0]
    print('IP: ', ip)
 
# Connect to Blynk
blynk = BlynkLib.Blynk(BLYNK_AUTH)
 
# Initialize the relay pins
relay1_pin = Pin(1, Pin.OUT)
led_pin = Pin("LED", Pin.OUT)

 
# Register virtual pin handler
@blynk.on("V1") #virtual pin V1
def v1_write_handler(value): #read the value
    if int(value[0]) == 1:
        relay1_pin.value(1) #turn the relay1 on
    else:
        relay1_pin.value(0) #turn the relay1 off
        

@blynk.on("V2") #virtual pin V1
def v2_write_handler(value): #read the value
    if int(value[0]) == 1:
        led_pin.value(1) #turn the relay1 on
    else:
        led_pin.value(0) #turn the relay1 off
 

 
while True:
    blynk.run()

Photos of IOT plant watering system

IOT Plant watering project working photo

Working Video of IOT plant watering