• Home
  • Archive
  • Tools
  • Contact Us

The Customize Windows

Technology Journal

  • Cloud Computing
  • Computer
  • Digital Photography
  • Windows 7
  • Archive
  • Cloud Computing
  • Virtualization
  • Computer and Internet
  • Digital Photography
  • Android
  • Sysadmin
  • Electronics
  • Big Data
  • Virtualization
  • Downloads
  • Web Development
  • Apple
  • Android
Advertisement
You are here: Home » How to Control Multiple Relays With Single Arduino ESP32?

By Abhishek Ghosh September 7, 2019 8:35 am Updated on September 7, 2019

How to Control Multiple Relays With Single Arduino ESP32?

Advertisement

One regular reader of this website asked us how we can control multiple relays with single Arduino ESP32? This article will not give any direct answer. This is a theoretical article discussing how multiple channels on MQTT can be created so that we can separate matters like temperature and humidity from a DHT11 sensor. Normally we connect DHT11 with IBM Watson IoT in a raw manner. In our that linked guide, it is IBM Watson IoT platform which can separate data and create dashboard visualization. IBM Watson IoT platform and IBM Node-RED are almost bare bone – you can easily run the same setup on a Raspberry Pi or own server. IBM Watson IoT has minimum vendor lock-in. That is said. The Watson IoT Platform has specific requirements on what MQTT topics devices and gateways can use. The Watson IoT Platform is not intended for use as a generic MQTT broker.

How to Control Multiple Relays With Single Arduino ESP32

You can create too difficult things with Cayenne IoT with few clicks but you will get vendor lock-in. It is just a few lines of codes with Cayenne IoT :

Vim
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
#define CAYENNE_PRINT Serial
#include <CayenneMQTTESP32.h>
 
char ssid[] = "YourNetworkSSID";    
char wifiPassword[] = "networkpassword";  
char username[] = "MQTT_username";   //your MQTT username
char password[] = "MQTT_password";   //your MQTT password
char clientID[] = "CLIENT_ID";       //your clientID
 
const int Relay4 = 14;        
const int Relay3 = 12;      
const int Relay2 = 13;      
const int Relay1 = 15;      
 
void setup() {
  pinMode(Relay4, OUTPUT);
  pinMode(Relay3, OUTPUT);
  pinMode(Relay2, OUTPUT);
  pinMode(Relay1, OUTPUT);
 
  digitalWrite(Relay1, HIGH);
  digitalWrite(Relay2, HIGH);
  digitalWrite(Relay3, HIGH);
  digitalWrite(Relay4, HIGH);
 
  pinMode(LED_BUILTIN, OUTPUT);
  
  Serial.begin(9600);
  Cayenne.begin(username, password, clientID, ssid, wifiPassword);
  Serial.println("Ready..");
  digitalWrite(LED_BUILTIN, LOW);
}
 
unsigned long previousmillis = 0;
int setInterval = 5000;
 
void loop() {
  Cayenne.loop();
  
  unsigned long currentmillis = millis();
  if (currentmillis - previousmillis > setInterval) {
   digitalWrite(LED_BUILTIN, LOW);        
   Cayenne.virtualWrite(6, WiFi.RSSI());  
   digitalWrite(LED_BUILTIN, HIGH);
   previousmillis = currentmillis;
  }
  
}
 
CAYENNE_IN(0)  // action for channel 0
{
  CAYENNE_LOG("CAYENNE_IN_DEFAULT(%u) - %s, %s", request.channel, getValue.getId(), getValue.asString());
  getValue.setError("Error message");
  if(getValue.asInt()) {
    digitalWrite(LED_BUILTIN, HIGH);
    delay(1000);
    digitalWrite(LED_BUILTIN, LOW);
    delay(1000);
    digitalWrite(LED_BUILTIN, HIGH);
    delay(1000);
    digitalWrite(LED_BUILTIN, LOW);
    delay(1000);  
  }
}
 
CAYENNE_IN(1)
{
  CAYENNE_LOG("CAYENNE_IN_DEFAULT(%u) - %s, %s", request.channel, getValue.getId(), getValue.asString());
  getValue.setError("Error message");
  if(getValue.asInt()){
      Serial.println("SwitchON 1");
      digitalWrite(Relay1,0); //Device will be SwitchON
    }
  else {
      Serial.println("SwitchOFF 1");
      digitalWrite(Relay1,1); //Device will be SwitchOFF
    }
}
 
CAYENNE_IN(2)  
{
  CAYENNE_LOG("CAYENNE_IN_DEFAULT(%u) - %s, %s", request.channel, getValue.getId(), getValue.asString());
  getValue.setError("Error message");
  if(getValue.asInt()){
      Serial.println("SwitchON 2");
      digitalWrite(Relay2,0); //Device will be SwitchON
    }
  else {
      Serial.println("SwitchOFF 2");
      digitalWrite(Relay2,1); //Device will be SwitchOFF
    }
}
 
CAYENNE_IN(3)  
{
  CAYENNE_LOG("CAYENNE_IN_DEFAULT(%u) - %s, %s", request.channel, getValue.getId(), getValue.asString());
  getValue.setError("Error message");
  if(getValue.asInt()){
      Serial.println("SwitchON 3");
      digitalWrite(Relay3,0); //Device will be SwitchON
    }
  else {
      Serial.println("SwitchOFF 3");
      digitalWrite(Relay3,1); //Device will be SwitchOFF
    }
}
 
CAYENNE_IN(4)  
{
  CAYENNE_LOG("CAYENNE_IN_DEFAULT(%u) - %s, %s", request.channel, getValue.getId(), getValue.asString());
  getValue.setError("Error message");
  if(getValue.asInt()){
      Serial.println("SwitchON 4");
      digitalWrite(Relay4,0); //Device will be SwitchON
    }
  else {
      Serial.println("SwitchOFF 4");
      digitalWrite(Relay4,1); //Device will be SwitchOFF
    }
}

But, you can see that you never learn how the CAYENNE_IN working. The code is enough to get the work done but it escapes the required steps of learning “how I can make it working”.

Advertisement

---

The reader liked our IBM IoT smart switch guide and ESP32 glass touch buttons.

The answer to the actual question as theory is not that easy. For that reason, I am preparing the readers stage by stage, like how to control a fan over IoT. It is not easy to create a smart switch panel compared to a single smart switch. There are other technical matters, apart from just the code. AC connection is dangerous.

Before we learn to control multiple relays with single Arduino ESP32, we need to learn how to create multiple MQTT channels & fetch data. Code for generic version BME280 sensor module will go like this :

Vim
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
#include <WiFi.h>
#include <PubSubClient.h>
#include <Wire.h>
#include <Adafruit_BME280.h>
#include <Adafruit_Sensor.h>
 
// Replace the next variables with your SSID/Password combination
const char* ssid = "REPLACE_WITH_YOUR_SSID";
const char* password = "REPLACE_WITH_YOUR_PASSWORD";
 
// Add your MQTT Broker IP address, example:
//const char* mqtt_server = "192.168.1.144";
const char* mqtt_server = "YOUR_MQTT_BROKER_IP_ADDRESS";
 
WiFiClient espClient;
PubSubClient client(espClient);
long lastMsg = 0;
char msg[50];
int value = 0;
 
//uncomment the following lines if you're using SPI
/*#include <SPI.h>
#define BME_SCK 18
#define BME_MISO 19
#define BME_MOSI 23
#define BME_CS 5*/
 
Adafruit_BME280 bme; // I2C
//Adafruit_BME280 bme(BME_CS); // hardware SPI
//Adafruit_BME280 bme(BME_CS, BME_MOSI, BME_MISO, BME_SCK); // software SPI
float temperature = 0;
float humidity = 0;
 
// LED Pin
const int ledPin = 4;
 
void setup() {
  Serial.begin(115200);
  // default settings
  // (you can also pass in a Wire library object like &Wire2)
  //status = bme.begin();  
  if (!bme.begin(0x76)) {
    Serial.println("Could not find a valid BME280 sensor, check wiring!");
    while (1);
  }
  setup_wifi();
  client.setServer(mqtt_server, 1883);
  client.setCallback(callback);
 
  pinMode(ledPin, OUTPUT);
}
 
void setup_wifi() {
  delay(10);
  // We start by connecting to a WiFi network
  Serial.println();
  Serial.print("Connecting to ");
  Serial.println(ssid);
 
  WiFi.begin(ssid, password);
 
  while (WiFi.status() != WL_CONNECTED) {
    delay(500);
    Serial.print(".");
  }
 
  Serial.println("");
  Serial.println("WiFi connected");
  Serial.println("IP address: ");
  Serial.println(WiFi.localIP());
}
 
void callback(char* topic, byte* message, unsigned int length) {
  Serial.print("Message arrived on topic: ");
  Serial.print(topic);
  Serial.print(". Message: ");
  String messageTemp;
  
  for (int i = 0; i < length; i++) {
    Serial.print((char)message[i]);
    messageTemp += (char)message[i];
  }
  Serial.println();
 
  // Feel free to add more if statements to control more GPIOs with MQTT
 
  // If a message is received on the topic esp32/output, you check if the message is either "on" or "off".
  // Changes the output state according to the message
  if (String(topic) == "esp32/output") {
    Serial.print("Changing output to ");
    if(messageTemp == "on"){
      Serial.println("on");
      digitalWrite(ledPin, HIGH);
    }
    else if(messageTemp == "off"){
      Serial.println("off");
      digitalWrite(ledPin, LOW);
    }
  }
}
 
void reconnect() {
  // Loop until we're reconnected
  while (!client.connected()) {
    Serial.print("Attempting MQTT connection...");
    // Attempt to connect
    if (client.connect("ESP8266Client")) {
      Serial.println("connected");
      // Subscribe
      client.subscribe("esp32/output");
    } else {
      Serial.print("failed, rc=");
      Serial.print(client.state());
      Serial.println(" try again in 5 seconds");
      // Wait 5 seconds before retrying
      delay(5000);
    }
  }
}
void loop() {
  if (!client.connected()) {
    reconnect();
  }
  client.loop();
 
  long now = millis();
  if (now - lastMsg > 5000) {
    lastMsg = now;
    
    // Temperature in Celsius
    temperature = bme.readTemperature();  
    // Uncomment the next line to set temperature in Fahrenheit
    // (and comment the previous temperature line)
    //temperature = 1.8 * bme.readTemperature() + 32; // Temperature in Fahrenheit
    
    // Convert the value to a char array
    char tempString[8];
    dtostrf(temperature, 1, 2, tempString);
    Serial.print("Temperature: ");
    Serial.println(tempString);
    client.publish("esp32/temperature", tempString);
 
    humidity = bme.readHumidity();
    
    // Convert the value to a char array
    char humString[8];
    dtostrf(humidity, 1, 2, humString);
    Serial.print("Humidity: ");
    Serial.println(humString);
    client.publish("esp32/humidity", humString);
  }
}

You can see that we have two topics :

Vim
1
2
3
4
5
…    
client.publish("esp32/temperature", tempString);
…
client.publish("esp32/humidity", humString);
…

Home Assistance is a bigger hammer and there are a lot of tools/platforms such as :

Vim
1
https://www.home-assistant.io/

I can show you another code to give an idea how to handle multiple relays :

Vim
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
#include <PubSubClient.h>
#include <WiFi.h>
// #include <ArduinoOTA.h>
 
void callback(char* topic, byte* payload, unsigned int length);
#define MQTT_SERVER "xxx.xxx.xxx.xxx"  //you MQTT IP Address
const char* ssid = "YOUESSID";
const char* password = "WIFI_PASSWORD";
 
const int switchPin1 = D1;
const int switchPin2 = D2;
const int switchPin3 = D3;
const int switchPin4 = D5;
 
char const* switchTopic1 = "/house/switch1/";
char const* switchTopic2 = "/house/switch2/";
char const* switchTopic3 = "/house/switch3/";
char const* switchTopic4 = "/house/switch4/";
 
 
WiFiClient wifiClient;
PubSubClient client(MQTT_SERVER, 1883, callback, wifiClient);
 
void setup() {
  //initialize the switch as an output and set to LOW (off)
  pinMode(switchPin1, OUTPUT); // Relay Switch 1
  digitalWrite(switchPin1, LOW);
 
  pinMode(switchPin2, OUTPUT); // Relay Switch 2
  digitalWrite(switchPin2, LOW);
 
  pinMode(switchPin3, OUTPUT); // Relay Switch 3
  digitalWrite(switchPin3, LOW);
 
  pinMode(switchPin4, OUTPUT); // Relay Switch 4
  digitalWrite(switchPin4, LOW);
 
  ArduinoOTA.setHostname("My Arduino");
  ArduinoOTA.begin();
  //start the serial line for debugging
  Serial.begin(115200);
  delay(100);
 
  //start wifi subsystem
  WiFi.begin(ssid, password);
  //attempt to connect to the WIFI network and then connect to the MQTT server
  reconnect();
 
  //wait a bit before starting the main loop
      delay(2000);
}
 
void loop(){
 
  //reconnect if connection is lost
  if (!client.connected() && WiFi.status() == 3) {reconnect();}
 
  //maintain MQTT connection
  client.loop();
 
  //MUST delay to allow ESP8266 WIFI functions to run
  delay(10);
  ArduinoOTA.handle();
}
 
void callback(char* topic, byte* payload, unsigned int length) {
 
  //convert topic to string to make it easier to work with
  String topicStr = topic;
  //EJ: Note:  the "topic" value gets overwritten every time it receives confirmation (callback) message from MQTT
 
  //Print out some debugging info
  Serial.println("Callback update.");
  Serial.print("Topic: ");
  Serial.println(topicStr);
 
   if (topicStr == "/house/switch1/")
    {
 
     //turn the switch on if the payload is '1' and publish to the MQTT server a confirmation message
     if(payload[0] == '1'){
       digitalWrite(switchPin1, HIGH);
       client.publish("/house/switchConfirm1/", "1");
       }
 
      //turn the switch off if the payload is '0' and publish to the MQTT server a confirmation message
     else if (payload[0] == '0'){
       digitalWrite(switchPin1, LOW);
       client.publish("/house/switchConfirm1/", "0");
       }
     }
 
     // EJ: copy and paste this whole else-if block, should you need to control more switches
     else if (topicStr == "/house/switch2/")
     {
     //turn the switch on if the payload is '1' and publish to the MQTT server a confirmation message
     if(payload[0] == '1'){
       digitalWrite(switchPin2, HIGH);
       client.publish("/house/switchConfirm2/", "1");
       }
 
      //turn the switch off if the payload is '0' and publish to the MQTT server a confirmation message
     else if (payload[0] == '0'){
       digitalWrite(switchPin2, LOW);
       client.publish("/house/switchConfirm2/", "0");
       }
     }
     else if (topicStr == "/house/switch3/")
     {
     //turn the switch on if the payload is '1' and publish to the MQTT server a confirmation message
     if(payload[0] == '1'){
       digitalWrite(switchPin3, HIGH);
       client.publish("/house/switchConfirm3/", "1");
       }
 
      //turn the switch off if the payload is '0' and publish to the MQTT server a confirmation message
     else if (payload[0] == '0'){
       digitalWrite(switchPin3, LOW);
       client.publish("/house/switchConfirm3/", "0");
       }
     }
     else if (topicStr == "/house/switch4/")
     {
     //turn the switch on if the payload is '1' and publish to the MQTT server a confirmation message
     if(payload[0] == '1'){
       digitalWrite(switchPin4, HIGH);
       client.publish("/house/switchConfirm4/", "1");
       }
 
      //turn the switch off if the payload is '0' and publish to the MQTT server a confirmation message
     else if (payload[0] == '0'){
       digitalWrite(switchPin4, LOW);
       client.publish("/house/switchConfirm4/", "0");
       }
     }
}
 
 
void reconnect() {
 
  //attempt to connect to the wifi if connection is lost
  if(WiFi.status() != WL_CONNECTED){
    //debug printing
    Serial.print("Connecting to ");
    Serial.println(ssid);
 
    //loop while we wait for connection
    while (WiFi.status() != WL_CONNECTED) {
      delay(500);
      Serial.print(".");
    }
 
    //print out some more debug once connected
    Serial.println("");
    Serial.println("WiFi connected");  
    Serial.println("IP address: ");
    Serial.println(WiFi.localIP());
  }
 
  //make sure we are connected to WIFI before attemping to reconnect to MQTT
  if(WiFi.status() == WL_CONNECTED){
  // Loop until we're reconnected to the MQTT server
    while (!client.connected()) {
      Serial.print("Attempting MQTT connection...");
 
      // Generate client name based on MAC address and last 8 bits of microsecond counter
      String clientName;
      clientName += "esp8266-";
      uint8_t mac[6];
      WiFi.macAddress(mac);
      clientName += macToStr(mac);
 
      //if connected, subscribe to the topic(s) we want to be notified about
      //EJ: Delete "mqtt_username", and "mqtt_password" here if you are not using any
      if (client.connect((char*) clientName.c_str(),"mqtt_username", "mqtt_password")) {  //EJ: Update accordingly with your MQTT account
        Serial.print("\tMQTT Connected");
        client.subscribe(switchTopic1);
        client.subscribe(switchTopic2);
        client.subscribe(switchTopic3);
        client.subscribe(switchTopic4);
        //EJ: Do not forget to replicate the above line if you will have more than the above number of relay switches
      }
 
      //otherwise print failed for debugging
      else{Serial.println("\tFailed."); abort();}
    }
  }
}
 
//generate unique name from MAC addr
String macToStr(const uint8_t* mac){
 
  String result;
 
  for (int i = 0; i < 6; ++i) {
    result += String(mac[i], 16);
 
    if (i < 5){
      result += ':';
    }
  }
 
  return result;
}

Now, look at our code for previous guide :

Vim
1
2
3
4
5
6
…
#define CMD_STATE "/gpio/"
 
// use the '+' wildcard so it subscribes to any command with any message format
const char commandTopic[] = "iot-2/cmd/+/fmt/+";
…

Look at the “Subscribing to device commands” on official documentation from IBM.

We are sending the cURL request like this :

Vim
1
2
curl -u <yourApiKey>:<yourApiPassword> -H "Content-Type: text/plain" -v -X POST http://<yourOrg>.messaging.internetofthings.ibmcloud.com:1883/api/v0002/
application/types/<yourDeviceType>/devices/<yourDeviceId>/commands/gpio -d "on"

The last part of the command is important to notice :

Vim
1
<yourDeviceType>/devices/<yourDeviceId>/commands/gpio

The command is issued against the code :

Vim
1
2
3
...
#define CMD_STATE "/gpio/"
...

and the line o command topic is this :

Vim
1
2
3
4
5
…
 
const char commandTopic[] = "iot-2/cmd/+/fmt/+";
 
…

Just with cURL, you can control the whole house. We are communicating with the IoT agent ESP32 directly. We do not need to develop complex Android application. There are few guides on the internet like this one to do that with Sonoff device. IBM compiled Mosquitto in a way to make our work just easy for the server-side.

Tagged With blynk esp32 switch multiple relays , esp32 mqtt relay control , mutiple relay control using adrunio , esp32 single chnnel with multiple gpios , esp32 mysql error:109 , esp32 mqtt relay , esp32 cayenne 4 channel relay , esp 32 outputs to switch 4 x relays , controlling multiple devices esp32 , arduino multiple relays control

This Article Has Been Shared 573 Times!

Facebook Twitter Pinterest

Abhishek Ghosh

About Abhishek Ghosh

Abhishek Ghosh is a Businessman, Surgeon, Author and Blogger. You can keep touch with him on Twitter - @AbhishekCTRL.

Here’s what we’ve got for you which might like :

Articles Related to How to Control Multiple Relays With Single Arduino ESP32?

  • Send Basic Push Message from Arduino ESP32 using Blynk

    How to Send Basic Push Message from Arduino ESP32 using Blynk? With Blynk like web service & library, it is easy to create such basic project.

  • Connecting ESP32 Arduino with DHT11 with IBM Watson IoT

    Earlier, we described how to create graph on IBM Watson IoT dashboard by using the default widgets. In previous guide, we described how to use ESP32 Arduino with DHT11 sensor. Here is the Code and Diagram to Connect ESP32 Arduino with DHT11 with IBM Watson IoT and Get Odometer Like Gauges on Dashboard. For this […]

  • Scope of ESP32 in Commercial IoT Products

    Can ESP32 Used in Commercial IoT Products? Yes, ESP32 has modules and SoC to fit your production need. However, Arduino IDE is not for production.

  • Control ESP32 Arduino LED from IBM Watson IoT

    Here is How to Turn On and Off an LED Connected With ESP32 Arduino From IBM Watson IoT Using Simple Bash Scripts. You Can Use Relay Instead of LED.

  • Controlling AC Powered Appliances With ESP32 and IBM Watson IoT

    It is an upgrade to our previous article to control ESP32 Arduino LED from IBM Watson IoT. We already talked about Android Apps for Watson IoT for this purpose. We already have an article to use relay with Arduino. Our linked relay guide should be enough for anyone to understand how to use relay and […]

Additionally, performing a search on this website can help you. Also, we have YouTube Videos.

Take The Conversation Further ...

We'd love to know your thoughts on this article.
Meet the Author over on Twitter to join the conversation right now!

If you want to Advertise on our Article or want a Sponsored Article, you are invited to Contact us.

Contact Us

Subscribe To Our Free Newsletter

Get new posts by email:

Please Confirm the Subscription When Approval Email Will Arrive in Your Email Inbox as Second Step.

Search this website…

 

Popular Articles

Our Homepage is best place to find popular articles!

Here Are Some Good to Read Articles :

  • Cloud Computing Service Models
  • What is Cloud Computing?
  • Cloud Computing and Social Networks in Mobile Space
  • ARM Processor Architecture
  • What Camera Mode to Choose
  • Indispensable MySQL queries for custom fields in WordPress
  • Windows 7 Speech Recognition Scripting Related Tutorials

Social Networks

  • Pinterest (24.3K Followers)
  • Twitter (5.8k Followers)
  • Facebook (5.7k Followers)
  • LinkedIn (3.7k Followers)
  • YouTube (1.3k Followers)
  • GitHub (Repository)
  • GitHub (Gists)
Looking to publish sponsored article on our website?

Contact us

Recent Posts

  • Exploring the Benefits and Advantages of Microsoft’s Operating System March 22, 2023
  • Web Design Cookbook: Accessibility March 21, 2023
  • Online Dating: How to Find Your Match March 20, 2023
  • Web Design Cookbook: Logo March 19, 2023
  • How Starlink Internet Works March 17, 2023

About This Article

Cite this article as: Abhishek Ghosh, "How to Control Multiple Relays With Single Arduino ESP32?," in The Customize Windows, September 7, 2019, March 22, 2023, https://thecustomizewindows.com/2019/09/how-to-control-multiple-relays-with-single-arduino-esp32/.

Source:The Customize Windows, JiMA.in

PC users can consult Corrine Chorney for Security.

Want to know more about us? Read Notability and Mentions & Our Setup.

Copyright © 2023 - The Customize Windows | dESIGNed by The Customize Windows

Copyright  · Privacy Policy  · Advertising Policy  · Terms of Service  · Refund Policy

We use cookies on our website to give you the most relevant experience by remembering your preferences and repeat visits. By clicking “Accept”, you consent to the use of ALL the cookies.
Do not sell my personal information.
Cookie SettingsAccept
Manage consent

Privacy Overview

This website uses cookies to improve your experience while you navigate through the website. Out of these, the cookies that are categorized as necessary are stored on your browser as they are essential for the working of basic functionalities of the website. We also use third-party cookies that help us analyze and understand how you use this website. These cookies will be stored in your browser only with your consent. You also have the option to opt-out of these cookies. But opting out of some of these cookies may affect your browsing experience.
Necessary
Always Enabled
Necessary cookies are absolutely essential for the website to function properly. These cookies ensure basic functionalities and security features of the website, anonymously.
CookieDurationDescription
cookielawinfo-checkbox-analytics11 monthsThis cookie is set by GDPR Cookie Consent plugin. The cookie is used to store the user consent for the cookies in the category "Analytics".
cookielawinfo-checkbox-functional11 monthsThe cookie is set by GDPR cookie consent to record the user consent for the cookies in the category "Functional".
cookielawinfo-checkbox-necessary11 monthsThis cookie is set by GDPR Cookie Consent plugin. The cookies is used to store the user consent for the cookies in the category "Necessary".
cookielawinfo-checkbox-others11 monthsThis cookie is set by GDPR Cookie Consent plugin. The cookie is used to store the user consent for the cookies in the category "Other.
cookielawinfo-checkbox-performance11 monthsThis cookie is set by GDPR Cookie Consent plugin. The cookie is used to store the user consent for the cookies in the category "Performance".
viewed_cookie_policy11 monthsThe cookie is set by the GDPR Cookie Consent plugin and is used to store whether or not user has consented to the use of cookies. It does not store any personal data.
Functional
Functional cookies help to perform certain functionalities like sharing the content of the website on social media platforms, collect feedbacks, and other third-party features.
Performance
Performance cookies are used to understand and analyze the key performance indexes of the website which helps in delivering a better user experience for the visitors.
Analytics
Analytical cookies are used to understand how visitors interact with the website. These cookies help provide information on metrics the number of visitors, bounce rate, traffic source, etc.
Advertisement
Advertisement cookies are used to provide visitors with relevant ads and marketing campaigns. These cookies track visitors across websites and collect information to provide customized ads.
Others
Other uncategorized cookies are those that are being analyzed and have not been classified into a category as yet.
SAVE & ACCEPT