How to Control relay connected with esp 12e by mqtt - mqtt

Esp12 e connected with pic16f887 Microcontroller.while relay is connected with same esp 12e gpio pin.
Now, i want to control as well get status of this relay on my android app from anywhere in world.
I want to use MQTT WITHOUT raspberry pi.
How can I do that?

As per this answer, you could use your ESP to host an mqtt broker and then use an mqtt app on your android device to control the relay.
However, that is a terrible way to do things. There are two alternatives I would reccomend:
Use a web hosted mqtt server.
Communicate directly with the ESP with a simple HTTP api.
Without more specifics about your use-case, its difficult to suggest anything more relevant.

Related

Can devices connected to the same Wi-Fi communicate with each other without using data for accessing the internet?

I need to enable multiple devices to communicate with each other using OSC protocol which runs over IP protocol etc.
I have two wireless routers, one of them is capable of providing internet access from SIM card.
What I want to accomplish is:
provide all devices wireless connection for communication between each other
provide all devices connection to the Internet
avoid spending data from SIM card when my devices communicate with each other
This last point is what I can't solve - in my mind it should not be a problem. If I understand it correctly, I am creating a WLAN and there is no need for passing the data to the internet provider (or asking for data from him) and the router should act like a switch and route the signal from one device to another one if the IP and port is correct.
I have router TP-Link Archer C6 ; router TP-Link Archer MR200 ; Windows laptop ; Android phone ; iPad.
What I want to accomplish is remote control of DAW Reaper (running on Windows laptop) over Web Control Surface or OSC Protocol with TouchOSC app or Open Stage Control app.
I will appreciate any help!
Thank you very much in advance,
Peter

Internet connection problem from different network for NodeMCU ESP8266 which I am using for IOT home automation

Would anyone like to help me with this problem please?
how to connect/control Nodemcu esp8266 wi-fi module from different network for control iot devices from outside of any home/ house?
Internet connection problem from different network for NodeMCU ESP8266 which I am using for IOT home automation.
Actually, in case of an class project, I have used some code (also coppied some code and took help from some website) from internet and also used Blynk for controll my ESP8266.
But not i want to make a personal app by which app I can control my devices outside from my home.
I have already connected with my WI-FI router with my home network!!
It worked well,
But i don't know how to do the same thing from different netwrok.
If possible I think anyone can help me....
Thank you.
To everyone.
This has been answered in greater detail on both the Arduino and Internet of Things StackExchange sites. In summary:
For safety, it is difficult to start a connection to a device on another local network. Devices on WiFi networks are protected from the Internet by a firewall, which is normally configured to return responses to requests sent by the devices, but block all unsolicited messages. Even if the firewall allows an incoming connection on a given port, "port forwarding" or other custom configurations are needed for unexpected messages to reach one of the multiple devices on the network (the devices usually share the same public IP address of the network and external systems' messages cannot reach the right local address without forwarding by the router).
Any device exposed to unsolicited requests like this is at risk of being attacked and can pose a risk to other systems on the network. It is thus safer to leave the firewall the same and instead make the device subscribe to an external webserver, which acts as a mailbox for incoming messages. Then, you can send requests to the server from anything with an internet connection, and the server will store them and relay them to the ESP8266 whenever the ESP asks. MQTT protocol using a server-side broker program like Mosquitto and a client like PubSubClient on your ESP8266 could work for this sort of publish-subscribe model, and MQTT tutorials and explanations are available both on both tool sites and Stack sites.
You can use Arduino IDE to program ESP8266 device.
https://randomnerdtutorials.com/how-to-install-esp8266-board-arduino-ide/
After installing ESP8266 in Arduino IDE. You need to connect ESP8266 with WiFi router(which have internet connected). Once your device is connected with a WiFi router. you can MQTT protocol to communicate with the server. You can use the following library in Arduino to implement MQTT client in ESP8266. ESP8266 is used to send and receive data from a different network. ESP8266 is subscribed to a particular topic. You can publish data to that topic from different MQTT client.
https://github.com/Imroy/pubsubclient
Use the Following link to get more familiar with MQTT protocol
https://www.hivemq.com/blog/mqtt-essentials-part-1-introducing-mqtt
You can use MQTTfx desktop application to send and receive data from NodeMcu(ESP8266).
MQTT basic diagram for understanding

How to link/pair HTML 5 with a hardware device?

I have two entities which I would like to be able to start a communication:
Hardware Device Using Atmel ATSAMS70 and WINC1500 Wifi Module
HTML 5 App
The idea to have a HTML 5 app is to be able to communicate easily with most of the commercial devices like: Windows computers, Android Phones, Mac OSX computer and iOS devices. Apart from that, I would avoid working with native code at all.
Currently, they can talk with each other using WebSockets but somehow the IP address of the custom board has to be known from HTML 5 to initiate the communication.
In order to do this, I can think of 3 options:
Using WebRTC I can get the local IP address of the browser and then I could do a scan of the local devices considering a 255.255.255.0 network mask.
Have an external server that the hardware device can send its local address which will be later retrieved by HTML 5.
Using Bonjour or some sort of device discovery service between the board and HTML5.
I could not find a way to achieve #3 but #2 seems feasible to me. #1 is what I am doing now, but WebRTC is currently not supported on iOS.
So, is there any other better possibility to achieve this communication?
You don't mention how the WINC1500 unit is being connected to the network but presumably this is in STA mode (acting as a wifi station rather than becoming a software access point or part of an ad-hoc network) and is being provided with its IP details through an existing access point?
Ordinarily I'd suggest that once connected, the device ought to start indicating its availability on the network via a regular UDP broadcast on a specific port but my (admittedly limited) understanding of WebSockets it is that it creates TCP connections. The only implementation of Bonjour that I've seen uses UDP messaging too, that may be why you've had trouble with your third approach.
Your second approach seems more likely to work well. A server at a known (or discoverable) IP on the local network which allows the Atmel device to register itself (and its IP address) and also allows other applications (your HTML 5 WebSockets applications) to request that connection information to allow them to create the WebSocket TCP connections they need.
I suppose that doesn't really answer your question as to "Is there a better way?", other than to say "Not that I can think of, your second approach looks good to me...". Sorry! Sounds like a very interesting project, overall,

Real-time data from Raspberry Pi to iPhone

I recently have not much experiance about working with a raspberry.
I need to send real-time data from my Raspberry Pi 2 Model B to an iPhone. The Raspberry will get the internet connection via UMTS stick.
I thought about a websocket but I didn't find any information what websocket would be the best and how to config it.
So is there anyone who already has a solution about it?
Thank you!
WebSocket requires a WebSocket (WS) server or a webserver that understands the WebSocket protocol as defined by the IETF. So for a RPi to talk directly to your iPhone, one of the devices has to have a WS server... which is not likely.
There are a couple of possible alternatives (there are certainly others). You could send data from the RPi to an external server that hosts a WS-capable server which then forwards that data to your iPhone, either thru a native app or a web browser. The data is logically transmitted between the two devices, but physically sent using an external service to coordinate the two. Visit http://goo.gl/Utg0dU to see data exchanged between an RPi and an iPhone using web messaging (src available).
Another possible alternative is to use Bluetooth to send data directly from the RPi to the iPhone. Being a Java dude, I know you can run a JVM on the RPI and I know there's a Java bluetooth API, and obviously the iPhone supports bluetooth, so its definitely do-able with a JVM. A quick Google shows plenty of support for bluetooth on the RPi with other languages. So you're good with this approach too.
If the Raspberry Pi is connected to the Internet with a public IP Address (I guess it doesn't since it uses UMTS) then you can setup a TCP Listener where the iPhone will connect to. If it doesn't and you can do Port Forwarding (I guess you can't) then you can forward the TCP port to the Raspberry Pi. The above examples also work with an HTTP server.
If the iPhone is near the Raspberry Pi and you're writing an app for the iPhone you can use a Bluetooth transceiver on the Pi to communicate.
If you can't do any of this you may need a third server with a public IP where both devices will connect to and the server will relay all connections from one device to the other.
In general, it would help if you could describe a little bit better what you want to achieve and the network topology involved so we can provide more specific answers.

How do I communicate between devices connected to a WiFi Access Point?

I have got a couple of phones and another couple of PC's connected to a Wifi access point and need to send and receive messages between either of these, I mean anyone can send a message to anyone and receive a message from anyone.
I am willing to write apps on the phones(Symbian OS, S60 platform) or PC(Windows), but what I can't understand is how do I set up a client or server, since any one of these devices could be a client or server.
If I use sockets do I have to script for ServerSockets and also Sockets on each of these devices? Can I use the HTTP protocol?
Alternatively any standard protocol that I could use to implement this?
You would broadcast UDP packets which would arrive at every device on the Wifi network. You would have to invent your own protocol to decide on the identity of each device, since you wouldn't be able to easily infer the IP addresses of your network devices. Without writing an election algorithm you would find it difficult to use a client/server architecture, so just use point-to-point (P2P).
Google for UDP broadcasts and read the relevant RFCs at ietf.org.
It seems like you're looking for pretty typical peer-to-peer communication over IP. I suppose other requirements will dictate which transport you use (HTTP, raw sockets, etc), but yes: Each node will be both a client and a server. You could possibly use MDNS (http://www.multicastdns.org/) to help the nodes find eachother in an ad-hoc manner.

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