I'm new to Arduino.
I have 4 Arduino boards separated by long distance. I wanted to make connections between all of them so, for example if one sensor connected to Arduino board number 1 (for example) was triggered it will send to all other 3 boards some kind of notification to do action on other boards. I intended to use Ethernet shield but wondered what is the best mode to use when configuring Ethernet Shields with Arduino and how to configure them to do so . I hope you understand. Thank you in advance.
On Arduino with a networking shield you can start an EthernetServer or WiFiServer. See ChatServer example of the Ethernet library.
On other Arduino with a networking shield you create an EthernetClient (or WiFiClient) and connect it to IP address of the server. Then everything you print to client's Client will be send to server's Client returned by server.available().
You can test the server with a Telnet client.
Related
I want to program a simple Webserver with an ESP8266 but I want to connect the ESP8266 to an Arduino Mega. I want to connect a LED and a Sensor to the Arduino and control the LED and read the sensor data via the ESP8266 Webserver.
I am a beginner and dont want too complex solutions. It's just a simple school project.
For the Webpage I am sending just some HTML Code, I do not use Blynk or anything like that.
My question is how can I connect the ESP8266 to the Arduino and control it's pins?
There is a million ways to connect an ESP to an Arduino.
Without any shields or perihperals you can basically use any wired bus that does not require transceivers.
For example I2C or SPI.
With shields or peripherals you can use CAN, LIN, RS232, Ethernet, WIFI, Bluetooth, radio, optical and audio transmission... The list is endless.
You can of course read a sensor with the ESP so an Arduino Mega is not really necessary.
I am trying to connect a WiFi module (ESP8266) to a "funduino" development board (Arduino Nano) but I have no success. Since I tried so much schematics I've found on the internet about the connection between them two, I kindly ask here if is anyone who succeed in "pairing" this two devices.
I am asking for the schematic and a functional source code.
Regards
The ESP-01 by default comes with nonOS SDK bootloader that communicated via AT commands, you can find the complete command set from Expressif here. This is designed for an MCU (like Arduino Nano) to use it purely as an WiFi module rather than using it as a stand-alone MCU (for which it will require NodeMCU SDK).
If you ever upload an Arduino sketch up to the ESP-01, it will erase the AT Command firmware.
Assuming your ESP-01 is still having the AT Command firmware. What #Ben provided is a sketch that allows you to type AT commands via the Serial Monitor to internact with the ESP-01, it is manual, and good for testing if ESP-01 is working (you type AT and press return on Serial Monitor, the ESP-01 will ack with Ok) but not practical as a real application. The minimum commands required to established an WiFi connection with ESP-01 is listed below.
AT+CIPMUX=1 - Enable single (0) or multiple connection (1) to the web server.
Multiple connection is a good option if you are repeatedly sending
out or reading data from the Internet.
AT+CWMODE=3 - Set WiFi mode: 1 is station mode (ESP8266 is client), 2 is AP mode
(ESP8266 acts like a WiFi router where your phone or PC can connect),
3 is AP+station mode (make the ESP8266 do both)
AT+CWJAP=“<your-ssid>”,”<your-pw>” - Connect to your WiFi. Provide your SSID name
and password inside the double qoutes.
AT+CIFSR - This returns the IP address of the module, indicating that it has
successfully connected to your WiFi router.
Once the WiFi connection is established, you can further communicate with the ESP-01 via the connection, like accessing a website for example:
AT+CIPSTART=0,"TCP", "www.example.com","80” - Start TCP or UDP connection. The
0 is the id of the connection.
AT+CIPSEND=0,16 - Command to tell the module data is ready to be sent. 0 is the
connection id, and 16 is the length of the data to be sent.
After this command, the ESP8266 will reply with the “>”
character to tell us that it will be waiting for the data to be
sent. If successful, the module will reply with “SEND OK”
GET / HTTP/1.1 - Send the http header, and other data, etc...
You can write your own sketch to automate those AT commands for interacting with with ESP-01 once you understand the AT commands required for establish a WiFi connection.
Here are two resources that I personally found extremely useful for doing more than connecting to WiFi.
STM32-ESP-01 Web Server - although this is for interfacing with STM32, the main difference is the pin assignment, so you should be able to port to Arduino easily.
MQTT via ESP-01
As for hardware interface, please noted that what #Ben provided is correct in principle, but you need to be aware that the ESP-01(ESP8266 to be precise) is a 3V3 MCU, so the connection is depended on what kind of host board you are using. If you are using Arduino Uno/Nano, both are having a 5V MCU, you will need a voltage divider (two resistors to drop the voltage to 3v3 before connecting to ESP-01) or a level shifter chip at least for the ESP-01 Rx pin to avoid the potential damage to the ESP-01.
I'm trying to write a simple code that sends a string to an xbee and one that sends the string back, I was able to do this with XCTU via console, but I want my arduino to send the string.
I was able to use a simple code that read my output from the serial monitor and sends it to an xbee connected via usb adapter, the problem is that I now wrote the code so it sends a predefined string like in the screenshot, but when I write into the monitor it still sends whatever I wrote instead of the static string. I'm also unable to read what I type into the xbee console from XCTU.
I'd love any assistance in this, I've tried uploading and resetting everything to no avail.
Screenshot of problem with the current code of the arduino on the left
You said you were using an Arduino to try to communicate with your XBee Zigbee module.
One thing you have to check is the connection between the TX and RX signals on the Arduino side and on the XBee Zigbee side.
I've helped someone on another forum who used this Seed Studio XBee shield :
If you look at the schematics of this shield, the XBee 'DOut' signal (Tx) is wired to the XB_TX line which can be connected to any of the AJ2 pin with a jumper.
Now on the Arduino side :
On this extract of the Arduino schematics, we can see that the ATMEGA UART has it's RX signal connected to pin 2 of the CPU which is wired to the IOL (AJ2) pin 0.
So, that means that on this shield, the jumper have to be placed between XB_TX and pin 0 of AJ2 to connect the XBee transmission signal (output) to the ATMEGA reception signal (input) [and also XB_RX have to be connected pin 1 of AJ2].
As you didn't mention what kind of shield you were using, you have to double check this point which is a common issue when using serial communication.
In a general way, ALWAYS connect 1 output to N input (except open-drain or open-collector outputs which can be connected together to make a wired OR but which finally have to be connected to N inputs)
Hope this helps
Best regards
From what I can tell on the documentation Xbee "hijacks" the serial system. Instead try blinking an LED to confirm data is being received and sent.
documentation
I need some guidance for making LED ON-OFF using Arduino Uno and GSM SIM900 with the help of internet data. Also how to setup free hosting server so that I can communicate my arduino with android app.
Step 1: set GPRS Commands(ie APN) of SIM900
Step 2: set tcp ip connection to your static server and port number(AT command is given in manual. static IP is must)
step 3: When TCP/IP connection gets ready, send command from server(use Hercules software) to your device to on/off led.
step 4: read server's command from your arduino and make led on/off.
I hope it help.
Is it possible to get sensor output from Arduino via Ethernet connection and to send data to Arduino via Ethernet?
So basically can "replace" serial port with Ethernet port?
The typical way to do this is with an Arduino Ethernet shield, a small hardware module that plugs into your Arduino board:
http://arduino.cc/en/Main/ArduinoEthernetShield
Updated:
One very common approach for client to server communication would be to use HTTP over TCP/IP. See this example on the Ardunio site of a simple client on an Ardunio connecting with a server (in this case google):
http://arduino.cc/en/Tutorial/WebClient
For your use case you can simply create your own server and modify the example to send data to it.
Alternatively you can skip the HTTP part and just use sockets - there is an open source example here:
https://github.com/billroy/socket.io-arduino-client