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41

There are many different type of RF networks with various advantages and disadvantages. The main things I consider when choosing a wireless communication method are network topology, data rate and power consumption. WiFi: High data rate (54Mbit/s +) but also high power consumption. Used when you need to connect directly to the internet, such as an internet-...


26

You have a few options for connecting your Arduino to the network/Internet. Ethernet Something like the Arduino Ethernet Shield allows you to plug in an Ethernet cable from the wall or router into your Arduino. Obviously, the main limitation is that your device is now tethered by the cable. For outdoor use, I wouldn't do this. WiFi The Arduino WiFi ...


7

Yes. The serial port uses a ring buffer (also known as a circular buffer) for storing the incoming data until you want it. That buffer is 16 bytes in size on the smaller Arduinos and 64 bytes in size on the larger one. A similar ring buffer is used to store transmitted data until the port is ready to transmit it in the background.


5

Yes. As given in the datasheets, normal ATtinyX4/X5 chips can run with a supply between 2.7 and 5.5V inclusive, whereas the low-power versions can run between 1.8V and 5.5V. Mind the speed restrictions when running at lower voltages though; see the "Electrical Characteristics" section of each datasheet to determine the maximum characterized speed for a ...


5

This is part of a Fritzing circuit I used to control the x'mas tree lights (the relays and sensors have been snipped out) with an XBee. This circuit uses a 3.3v LDO you may have to change the capacitor values depending on your regulator specs. I chose to use a separate 5V regulator (not shown) but it will work off the Pro Mini's +5V power rail. There are ...


5

The biggest mistake people always make with serial communications of any form is to just send raw data over the connection. While you might just about get away with that on a 100% reliable direct serial connection over a short distance, as soon as you introduce anything with any form of uncertainty to it you are, as you have seen, doomed to failure. So you ...


4

Marry OpenWrt and your Arduino Get a small OpenWrt-capable router like "TP-Link TL-WR703N", flash it with the current stable version of OpenWrt and connect your Arduino to the router's USB port. This solution ist half or less of the cost of WiFi-shields and has far more power. ...and cheaper as a YÙN. Smart home automation webserver on OpenWRT ...


4

ESP8266 is a cheap 5$ wifi module with UART, SPI connectivity. This can be integrated with Arduino seamlessly either through the stock firmware using AT commands, or by writing custom firmware using the SDK provided and GIPO available. For more reference http://www.esp8266.com/


4

I agree with @Gerben - the nRF24L01+ would probably be the most suitable for your application. It should have enough range to go 15m through a few walls, and the cost is about as cheap as you can get. You can pick up cheap Chinese clone modules (not real nRF24L01+ but another chip that operates exactly the same) for around $2 each on eBay. I by them by ...


4

do { r = XBee.read(); Serial.print(r); } while (r != -1); Think about it. Since you tested for XBee.available() you will have at least one iteration of this loop. And then you do a second read, and print it, before finding that the second character is -1. You need to re-order your loop, or your tests. The second character will be what ...


3

The pin number 9 and 13 on the Xbee are DTR/RTS used for hardware handshaking. You can connect it to the interrupt pins on the Arduino and program the arduino to wake when the pulse changes. Enable the DTR/RTS feature from X-CTU and it should work. Check this for more information.


3

There are several things here: Increase your delay, you don't want to be sending the data that often, even if you only increase it to 100-200ms, although I'd recommend making it in the order of 1-30 seconds. You're reading in analog inputs which will be in the range of 0-1023 but your serial reads are in byte format (which will actually be reading the first ...


3

The only way I can think of accomplishing this without some sort of proximity sensor is to measure the signal strength of the XBees. From page 41 of the datasheet: DB (Received Signal Strength) Command AT Command: ATDB Parameter Range [read-only]: 0x17-0x5C (XBee), 0x24-0x64 (XBee-PRO) DB parameter is used to read the received signal ...


3

I've been working with xbee on the arduino and raspberry pi for a few months now. Whilst it does have it's issues and quirks, it is a great tool in the communication chain. It's not perfect but given the mesh side of it, for me it reaches further than my wifi and can even be more reliable (my raspberry pi with wifi occasionally drops out, however the ...


3

Bluetooth and Zigbee are two different communication protocols. The Xbee clones you are talking about a called BTbee. As far as im aware the BTbee modules are the same hardware/firmware wise as the hc05/hc06 modules. The only difference being the BTbee modules are in the Xbee footprint, allowing you to plug them into Xbee/Zigbee sockets.


3

What you have there is an XBee module. It is designed to plug into an XBee shield which then plugs into the Arduino. So you need to buy more. That's the bad news. The good news is that you have already bought the most expensive part, and the shield to go with it is pretty cheap. Numerous people make the shields, such as: Sparkfun Seeed DFRobot Also ...


3

You are probably just transmitting too fast. Your receiver is writing at least 80 bytes of debugging information (if I counted it right) for every 3 bytes of incoming data. Since both input and debug output happen at the same baud rate, this means the receiver can only cope with an input data rate equal to 3/80 = 3.75% of the nominal baud rate. I ...


2

You could try a Arduino Yun, it is like a Uno but it has a WiFi directly on the board. There is a part in the "Guide to the Arduino Yún" called "Configuring the onboard WiFi", that describes how to configure the WiFi.


2

I use Spark Core which is a very easy to use Arduino programming platform. This platform was built on the primus that WiFi should be easy to use and cheap. Can even program the Spark Core from anywhere, any time.


2

The "XBee" brand has two major types. Series 1 are the original ones, and are often NOT referred to by their series number. Series 2 are the newer mesh network brethren. Most XBee's and their clones are pin compatible (there is even a Bluetooth replacement 'Bee), thus any XBee shield or adapter can be used for either series. The difference is largely in ...


2

You really do need to provide information on the shield, there are many versions out there (and I own half of them ). In essence, unless you are using an alternate serial port (SerialN) or software serial, then YES, your XBee will be using the same lines as your Arduino. If you are using Serial.print or Serial.write to talk to the XBee, then that is a ...


2

I don't have a PRO to play with, but I just looked at the datasheet and it appears that it SHOULD timeout after 60 seconds If no serial transaction is initiated within a 60 second timeout period, the bootloader times out and returns to the menu. If the upload is interrupted with a power cycle or reset event, the EM250 will detect an invalid ...


2

If the second isn't working, it may be best to use the other 2. Especially on the Arduino with limited RAM, you will not have enough if you pass a full struct to a function. Passing a pointer is less memory-intensive, and if it works, use it!


2

Take a look at this library : https://code.google.com/p/xbee-arduino/ This is the XBee Library for Arduino, you will find simple sketch that are perfect bases for the application you're trying to do.


2

Since one end is a PC I would look into a Wifi shield for the arduino. That way you would not need any extra hardware on the PC side. You can get a Wifi shield for less than 2 xbee modules. But using wifi will require changes to your code since it won't be using the serial port for communication. Another wireless option that I have no personal experience ...


2

Sounds like your pots are not connected correctly and you pick up noise. The waveform you are seeing could be from the mains, or another source. Stray magnetic fields from transformers etc. can couple and be picked up by your circuit and you will notice them if your input is of high impedance. The atmosphere is also full of electromagnetic radiation from ...


2

The reason that it is printing characters with no input is that the readBytesUntil function has a timeout. If no new characters are received for a certain amount of time, "Serail.setTimeout()" seconds, it will just continue with the code. the default timeout is 1 second. The reason you are not receiving what you transmit (or at least a reason) is that the ...


2

I would suggest you to send bytes instead of "analog value". When you calculate your value, not sure why you use float and then convert it to int, but here is how i would do. Communicate to xbee via serial communication, send bytes to xbee(its even easier than "analog value"). Added if statment to print RPM every second. Here is my code: #include <...


2

Try a communication protocol with a , as a delimiter like: messageId,data1,data2,data3,....,dataN\n And use the Messenger library to parse it. See my answer on comms protocols here: Communication Protocol Best Practices and Patterns An how to use the Messenger library here: Send Processing color data into Arduino


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