I need to send data (an integer) from an Arduino to a C program on a PC. I know that the connection is fine, because with X-CTU works perfectly. I need to do this in AT mode but I don't know how to start.
If you're using the XBee modules in AT mode, then it isn't much different than what you'd have to do with a direct serial cable connection between the Arduino and PC. Look for sample programs demonstrating serial communications for both platforms.
Having the connection working with X-CTU is an excellent starting point, since you have confirmed that the radio modules are communicating correctly.
On the PC, you might want to look at this Open Source XBee Host Library on GitHub. It includes a sample program called "xbee_term" that demonstrates a simple serial terminal for using an XBee in AT mode. It also has a layered API to allow for easy use of XBee modules in API mode -- which you would need to use if the PC was going to communicate with multiple Arduino nodes running in AT mode.
As for sending an int, you can use sprintf() to format it as a string to send over the wireless link, and strtol() to convert it back to an int on the PC end.
Related
Firstly, I'll just give you a brief introduction about our project... its "Speech controlled Home Automation System" where we are controlling the Home appliances by the voice or speech commands. We're successfully done with the voice recognition module. But our problem is with achieving the communication between the transmitter {where the user gives the voice command} and receiver {where the home appliances are present} through WiFi i.e. we have got 2 ESP8266 12E modules interfaced with Arduino both at the transmitter and receiver side and these two WiFi modules need to be communicated(To interchange some data sent by Arduinos).So please let us know which Arduino code need to be used at transmitter side wifi module and at Receiver side wifi module and also about the header files or additional softwares(if any)to be used.
you can achieve this by starting one of wifi modules in Access Point Mode and the other one has to be set to Station Mode in order to connect to the first one.
In case you want to add a router, just set both ESP8266 modules to Station Mode and connect them to the router.
And then transfer any data you want through AT commands of ESP8266.
Here is the refrence to them.
https://room-15.github.io/blog/2015/03/26/esp8266-at-command-reference/
If you are newbie to Esp8266 and Arduino , this will help you.
http://www.teomaragakis.com/hardware/electronics/how-to-connect-an-esp8266-to-an-arduino-uno/
Good Luck !
I worked on a similar system a year ago. I was developing a remote controlled toy. My main difference was I used the ESP8266 without an Arduino attached.
One ESP worked as a a WiFi hotspot and the other connected to it, sending messages through UDP.
For some reason, I could not get the two ESP modules to connect (I think it was a problem with the board I had), but I sent messages from my computer, and it worked out fine. I will not burden you with all of the code, but here is the GitHub link.
All that needs to happen is they will be on the same WiFi network, and then you can use the ESP8266 WiFi library to send messages between the two. Like I said above, I used UDP, which is good for high speed, with no error checking. But there is also TCP (higher up, has error checking code), or you can use the server/client part of the library to set up a full web server and read/write data to it. Without knowing what type of data, I cannot comment on what would be the best method.
As for headers, you will need WiFi.h, and if you are using UDP you will need WiFiUdp.h
You should not need any external software besides the Arduino IDE.
I taught myself from scratch for this product, using two main resources: the Arduino library reference, and the docs on the ESP8266 Arduino GitHub page
how the bellow connection can be done , what the protocol that must be used to send bytes from computer through it's serial WiFi and receive the bytes in Arduino using ESP8266-01 WiFi Serial Transceiver Module.
computer AND esp8266 WITH arduino
It depends on what you want to accomplish, and what roles you want the computer and the arduino/esp combi to play. You can put the ESP in station or access point mode (or mixed), and have it talk to the arduino via the serial interface. The communication with the PC will indeed go via wifi/tcp protocol, but depending on your specific requirements you will have to decide one the roles. Then you can make the ESP a web client or a web server, mainly depending on the direction of the flow of information.
I assume you want to query the Arduino from the PC, in which you can send a HTTP/GET request from the PC to a simple web server on the ESP.
There are various examples in the Arduino examples that do just that to give you a start, available when you install the ESP library in the Arduino IDE, see: https://github.com/esp8266/Arduino
HTH
I recently completed this project with my Arduino (a fairly new hobby for me):
http://www.instructables.com/id/Make-a-24X6-LED-matrix/?ALLSTEPS
I can change the code to make whatever messages I want scroll accross the matrix but I thought it might be cool to have live information, like stock quotes, scroll accross. I think I could figure out how to do that except I would like to use it at work where there are lots of firewalls in place and I doubt Arduino software is on the approved list of programs. Is it possible to send messages to the Arduino through a USB without installing any drivers?
No it is impossible because data in Arduino is sent via serial command, the USB is only for convenience, but arduino work with FTD driver that emulate a serial connection. You should choose another type of connection bluetooth or wifi.
Hope this help you.
How can I send a string via serial communications from Java or Python? I have a very little arduino program that will recieve a CSV string of ints that each control different relays (I adapted it from their example).
I just got an Arduino, and I am trying to use it to open and close a relay remotely. I have it opening and closing the relay, no problem. But I really have no idea where to start as far as using serial communication.
I have a bluetooth dongle that I can connect to, but once I do that I'm lost.
Also, this is my first time using serial communications AND my first time using an Arduino. So I'm sorry if I am completely off on some of the things I am asking. All I know is what I've learned from Google.
Thank you very much
You can use any Java or Python serial port classes and methods. There is however one thing you need to be aware of.
The newer arduino's have a feature known as AutoReset. This works by connecting the DTR signal from the serial port to the Reset line on the chip using a capacitor or such. The IDE uses this to reset the board to activate the bootloader and initiate uploading code to the arduino. The serial monitor in the IDE is aware of this and does not toggle the DTR line when comunicating with the device (except when it initially connects).
There is are several ways to defeat this feature and you can read about them here.
As for actually comunicating with the device, there are several tutorials about serial communication in both Java and Python.
Pyserial includes the option to not use the DTR lines when opening a port.
Here is a website explaining how to use RXTX (a Java library) to comunicate with an Arduino
Best of luck.
I'm using an Arduino to read data from the web and display it. I can easily pass the data as serial using the supplied drivers, because they identify the COM port so I can send serial to the COM port.
However, I want to use 'real' USB techniques so the device can be plugged in and out like a normal USB device. I'm looking at using WinUSB as the driver. However, USB is all new to me. Is there an .inf file that uses WinUSB and an Arduino (I have an Uno)?
The lack of information on this is making me think I am going about this incorrectly.
Turns out that an Arduino Uno is not a genuine USB device.
It acts as a Serial to USB adapter. Consequently USB drivers don't talk to it.
I got round this by writing a sketch which reported back what device it was when it got the correct query from the PC.
On the PC I just iterated the Serial ports and sent the query to each port. The one that replied was the Arduino.
After that I record the port number and send serial data to the Arduino.
To learn the USB portion, maybe you could combine V-USB and the UNO?
Check out V-USB.
V-USB is a software-only implementation of a low-speed USB device for Atmel’s AVR® microcontrollers, making it possible to build USB hardware with almost any AVR® microcontroller, not requiring any additional chip.
While not necessarily Arduino, it may provide you the learning exprience you want, and let you use incorporate your UNO device.