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I need to read GPS coordinates using a VB.NET program directly from a GPS device connected to the computer via USB (bluetooth also OK but prefer USB). My constraints are:
The computer running the software is NOT connected to the internet. It is a stand-alone machine in a moving vehicle.
I need to be able to read GPS coordinates from the device while the vehicle moves and use the device to perform location-aware queries on a local database
The GPS device can be anything (e.g. Garmin GPS or GPS card without display), as long at it can be purchased off the shelf or over the internet.
The user group for this solution is quite small (about 40 users).
I have already checked out GPSGate (http://gpsgate.com/) and emailed my requirements to them. They replied, and I quote: "I am sorry but we have no product for you." (end of reply).
I also checked out Eye4Software) and tried using their demo product but it does not pick up my Garmin Nuvi via USB. They responded to my questions but unfortunately their OEM product is an ActiveX dll and I am looking for a .NET based solution.
So if anyone has a "home-grown" solution based on the .NET framework, that can be easily duplicated, I would really appreciate it. Many thanks!
Most of the USB GPS pucks will speak a standardized protocol called NMEA 0183. There are several .net protocols out there that decode this protocol, see here for some pointers to get started.
So, if when shopping around you just check that the device is able to generate NMEA you should be up and running in a minimum of time, and at a reasonable cost.
EDIT: a "gps puck" is a GPS receiver shaped more or less like a hockey puck, like this one
For in-car use there are specific versions that can be fixed onto the vehicle's roof
They are pretty common (many online shops carry them) but select them based on the chip that's inside, the popular Sirf Star 3 is still a solid performer, stable and accurate. I haven't had the chance to play with its successor, the Sirf Star 4 yet, and I'm not implying these are the only good chips around, only that I got most experience with this chip.
I'm looking for a GPS for a small class project. We want the smallest GPS possible and all we really need it to do is to give us longitude and latitude values when we poll it.
I tried looking at sparkfun, but since we haven't really worked with this type of hardware before, it's hard to know which kind we really want/what parts we need.
What We Need:
smallest possible
longest battery life
only need long and lat
able to be polled from some other device such as a mobile app or website
Thanks!
there are two paths to this, one is just get a bluetooth receiver, you will be able to poll it from a mobile phone or whatever. going to likely be as big as the phone, have the battery inside, etc. not sure how long it will last on one charge.
There are other solutions designed for putting in packages being shipped, better battery life, but their goal is as data loggers and not necessarily something you can cable up and poll and likely not wireless if that is what you are after.
Now if you want to build your own, and you already went to sparkfun, here is another path.
I know that leaving links in an answer at SO is bad...This was longer than a comment and will add some more info...
You want small you can go with this
https://www.sparkfun.com/products/11571
It is a GP-635T gps receiver, if you look at the picture it really is around the size of a quarter. 50 channel. Point it up the way they tell you, antenna is built in, just power it and it works.
You will need to hook up to it. It is the serial version not usb, in either case you need a cable like this.
https://www.sparkfun.com/products/10361
This link is to a cable with 6 or 8 inch pigtails, the gps receiver comes on a board with a not so uncommon connector on it, this cable allows you get at those connections, you only need three.
The datasheet on the sparkfun page or probably just search for the part number, you need to look at the UART TTL pinouts not the usb pinouts. Yo uneed 3.3 to 5.5volts to power it pin 2, pin 1 is ground. then pin 3 is txa serial out. This is where you get your data.
these are various solutions that will work
https://www.sparkfun.com/products/9873
https://www.sparkfun.com/products/718
http://jim.sh/ftx/
some soldering may be required. The above links are various solutions between $10 and $15 for ftdi usb to serial/uart break out boards. These will include 3.3v and ground and the rx pin is the receiver for the ftdi uart, you tie that to txa on the gps unit.
What you may not know and may be interested in is that almost universally gps units do their math magic and come up with the various items time, position (2d or 3d), speed, etc. And they output this data in a serial manner. search for NMEA or NMEA-0183. The data sheet for this and any other should give an indication of the default data rate (4800, 9600, 19200, etc baud) and what messages are sent. sometimes you can change the baud rate, sometimes you cant. The ftdi chips/boards are very flexible use a usb cable to plug in the board to a computer, configure your software or a dumb terminal program like minicom or hyperterm or teraterm or whatever (no parity, no hardware flow control) and the messages will appear usually once a second. Whether it is your car navigation, handheld gps, whatever, buried inside is some flavor of gps reciever (sparkfun will give you an indication of just how many different flavors there are and their selection is just scratching the surface) that outputs serial and the software in that unit is receiving that serial data and then doing its thing (mapping, navigating, etc). As with modems back in the day the ones you find in your cell phone might have some of the software/math done by the main processor in the phone to save on money, these libraries are not generally available, when you make the deal to buy thousands or millions of units they allow you to pay for the software to go with it along with your signature on a bunch of legal documents. I assume this is the case, that is how the ones in phones are down to $10 or so where these fully contained solutions are usually $50 to $100 in single quantities and likely not a lot cheaper in quantity.
Once powered, even if it says X number of seconds hot or cold to lock it doesnt always take that, sometimes if it has to search it may still take a while, the less metal you have around (like being in a building or the center of a car) the worse it is to the point it may not lock.
if you have an older garmin street pilot (that is otherwise dead I would hate to kill one of those if it is working) you can rip it apart and likely find a sirf III or other module in there, likely a 5V not 3.3 (there are 5V ftdi based breakout usb to serial. the microftx is both 5v and 3.3, note the gps receiver linked above is also 5v or 3.3) googling will be required to figure out the pinout and such, and soldering might or might not be a challenge.
you can also find old etrex or other handhelds on ebay or wherever (that work!) and for $15 or so get a serial cable, well then you need a serial to usb likely which will also need a level shifter like a max232, you dont plug this right into a ftdi break out board, it will fry it. newer ones have usb and you can power the unit from the usb and likely see the nmea data over the usb as well.
Most of the stuff you see on sparkfun in the gps area is going to be related to these various brands and models of gps recivers that output nmea data over serial. some are 5V some are 3.3, many do not have antennas and you have to buy those separately (and get the right kind, one that plugs into the connector provided, etc). I have a number of these items and they all work just fine, some do better than others around buildings or in trees, etc. Around sparkfun you will also find lipo battery solutions and bluetooth or xbee or other wireless solutions, very quickly if you need wireless, I think you will find just buying an off the shelf solution is best. I have had my eye on the garmin bluetooth thing google
Garmin GLO Portable GPS and GLONASS Receiver
it is about $99. I have not pulled the trigger yet so I dont know how good or bad it is, the el cheapo brands just look cheap.
Of course, a smart phone has both wireless and a gps and you can get a lot of used phones for cheap on ebay. Ios and android. You could "just write an android app" and put it on the phone and use one of the wireless interfaces built into the phone. It will chew through the battery yes, how fast? who knows.
I'm not interested in a hardware solution, I want to know about software that may "read" modulated signal received trough the power supply - some sort of a low-level driver that would access the power signal in a convenient place and demodulate it.
Is there a way to receive signal from the computer's power supply? I'm interested in an API or library that would allow the computer to be seen as a node in a Power Line Communication network and receive data directly through the power cable, without the need for a converter. Is there any active research in this field?
Edit:
There is software that reads monitors and displays internal component voltages - DC voltage after being converted and filtered by the power supply - now I need is a method of data encoding that would be invariant to conversion and filtering, the original signal embedded in AC being present in some form within the converted DC signal.
This is not possible, as described in the question. Yes, with extra hardware you can do it. No, with the standard hardware in a PC, you could not.
As others have noted, among other problems, the only information you can get from a generic PC is a bit of voltage info for the CPU. It's not going to give a picture of the AC signal, nor any signal modulated on top of it. You'll be watching a few highly regulated DC signals deep inside the computer, probably converted at a relatively low rate too. Almost by definition, if you could see external information on any of those signals, your machine is already suffering a hardware failure and chances are the CPU will be crashing soon...
*blink* No...
Edit: I mean, there's the possibility to use the powerlines as network cables, but only with special adapters. And it is just designed for home networks.
Edit2: You can't read something from the power supply of a computer...it's not designed for that. You would have to create your own component/adapter for this.
Am I mis-reading this? Wouldnt this be a pure hardware solution?
This is highly improbable without adding some hardware.
You see, the power supplies in a regular PC are switching power supplies which effectively decouple the AC input from the supplied DC voltage needed on the PC side. The AC side just basically provides power that fuels the high-speed power switching circuitry.
Also, a DC signal, by definition, doesn't provide a signal per se: it is a "static" power level (and yes the power level does vary a bit in the time domain but not as an easy to leverage function).
Yes there can be an AD (Analog to Digital) monitoring chip that can be used on the PC side to read the voltage of the DC component supplied to the motherboard etc., but that doesn't mean there is still a signal that can be harvested: the original power line "signal" might have been through enough filters that there isn't a "signal" left to be processed.
Lastly, one needs to consider that power supplies design varies from company to company; this fact will undoubtedly affect any possible design of a communication solution.
what you describe is possible but unfortunately, you need an adapter to convert the signal running on the powerlines to sensible network traffic.
the power line acts as a physical medium, thus is at the lowest level f the OSI stack. conversion from electrical signal to sensible network traffic requires a hardware adapter, same for your an ethernet adapter. your computer is unable to understand this traffic since its power supply was not build to transmit those informations. but note that you can easily find an adapter and it will works the same as an ethernet adapter, that is be accessible through the standard BSD socket library.
This is ENTIRELY possible, although you would need to either buy or build some hardware to make it happen. In addition, the software solution would be very, very complex.
The computer's power supply would be out of the picture for the most part. You need to read data straight from the wall with as little extraneous noise as possible. From the electrical engineering perspective, this is a very thoroughly covered topic. In the end, all you're really doing is an analog to digital conversion, and the rest keeps your circuit from being fried.
The software solution would basically be eliminating random noise, and looking for embedded signals. The math behind analog signal analysis is very complex, and you can spend a few semesters in college covering the topic, and the rest of your career trying to master it. If you're good at it, there's a cushy job for you on wallstreet predicting the stock market.
And that only covers reading incoming signals. Transmitting is a whole 'nother sport.
Now, it also sounds like you might be interested in a hack. That is...
You could buy a
commercial-off-the-shelf power-line
Ethernet adapter and tear it apart.
They have two prongs that plug into
a standard wall outlet. You could
remove these and wire them to the
INSIDE of a power supply.
To do that, you'd have to tear apart a power
supply as well, which is incredibly
dangerous and I hereby warn you and
anyone else to NEVER attempt this.
The entire Ethernet adapter could be
tucked into the power supply and you
could basically have an Ethernet
port on the surface of your power
supply (either inside or outside the
computer).
Simply wire that to a
standard Ethernet adapter and voila
(!), you have nothing but a power
cable connecting your computer to
the wall outlet, AND you magically have
Ethernet!
Note that there also has to be another power-line
Ethernet adapter somewhere else for
you to establish a network and make the whole project useful.
How can you read modulated data from the power supply, you are talking about voltage and ohms and apart from a possible electrical shock which would be just shocking :) There are specialized electrical plugs with ethernet jacks in them that you can use.
I just hazard a guess that this is totally transparent as per Adrien Plisson's answer, i.e. you would have all of the OSI layer and is no different. You can write code to read from the sockets.
AFAIK no company that produces this electrical plug would ever open up the API for competition reasons, it is still in early stages as adoption of that is low because obviously it is very expensive (120 euro here in my country for a pair of 'em), as it does not deliver the quoted speed, say 100Mbps power plug, may get maybe 85Mbps due to varying situations and phenomena with power (think surges, brown outs, interference).
My 2cents.
Hope this helps,
Best regards,
Tom.
I'd like to start messing around programming and building something with an Arduino board, but I can't think of any great ideas on what to build. Do you have any suggestions?
I show kids, who have never programmed, or done any electronics before, to make a simple 'Phototrope', a light sensitive robot, in about a day. It costs under £30 (GBP) including Arduino, electronics and off-the-shelf mechanics. If folks really get into mobile robots, the initial project can grow and grow (which I feel is part of the fun).
There are international robot competitions which require relatively simple mechanics to get started, e.g. in the UK http://www.tic.ac.uk/micromouse/toh.asp
Ultimate performance require specially built machines (for lightness) , but folks would get creditable results with an Arduino Nano, the right electronics, and a couple of good motors.
A line following robot is the classic mobile robot project. The track can be as simple as electrical tape. Pololu have some fun videos about their near-Arduino 3PI robot. The sensors are about £1, and there are a bunch of simple motor+gearbox kits from lots of places for under £10. Add a few £ for motor control, and you have autonomous robot mechanics, in need of programming! Add an Infrared Remote receiver (about £1), and you can drive it around using your TV remote. Add a small solar cell, use an Arduino analogue input to measure voltage, and it can find the sun. With a bit more electronics, it can 'feed' itself. And so it gets more sophisticated. Each step might be no more than a few hours to a few days effort, and you'll find new problems to solve and learn from.
IMHO, the most interesting (low-cost) competitions are maze solving robots. The international competition rule require the robot to explore a walled maze, usually using Infrared sensors, and calculate their optimal route. The challenges include keeping track of current position to near-millimeter accuracy, dealing with real world's unpredictably noisy environment and optimising straight-line speed with shortest distance cornering.
All that in 16K of program, and 1K RAM, with real-time interrupt handling (as much as 100K interrupts/second for some motor systems), sensor sampling, motor speed control, and maze solving is an interesting programming challenge. (You might make it 'easy' with 32K of program, and 2K RAM :-)
I'm working on a 'constrained' robot challenge (based on Arduino) so that robot performance is mainly about programming rather than having a big budget.
Start small and build up to something more complex. Control servos. Blink LEDs. Debounce inputs. Read analog sensors. Display text on an LCD. Then put it together.
Despite the name, I like the "Evil Genius" book for PIC microcontrollers because of the small, easily digestible projects that tend to build on one another. It is, of course, aimed at PIC programmers rather than the Arduino, but the material covered will be useful no matter what you're developing on.
I know Arduino is trendy right now, but I also like the Teensy++ development board because of its low price-point ($24), breadboard-compatible PCB, relatively high pin count, Linux development environment, USB connectivity, and not needing a programmer. Worth considering for smaller projects.
If you come up with something cool, let me know. I need an excuse to do something fun :)
Bicycle-related ideas:
theft alarm (perhaps with radio link to a base station which is connected to a PC by Ethernet)
fancy trip computer (with reed switch or opto sensor on wheel)
integrate with a GPS telematics unit (trip logging) with Ethernet/USB download of logged data to PC. Also has an interesting PC programming component--integrate with Google Maps.
Other ideas:
Clock with automatic time sync from:
GPS receiver
FM radio signal with embedded RDS data with CT code
Digital radio (DAB+)
Mobile phone tower (would it require a subscription and SIM card for this receive-only operation?)
NTP server via:
Ethernet
WiFi
ZigBee (with a ZigBee coordinator that gets its time from e.g. Ethernet or GPS)
Mains electricity smart meter via ZigBee (I'm interested now that smart meters are being introduced in Victoria, Australia; not sure if the smart meters broadcast the time info though, and whether it requires authentication)
Metronome
Instrument tuner
This reverse-geocache puzzle box was an awesome Arduino project. You could take this to the next step, e.g. have a reverse-geocache box that gives out a clue only at a specific location, and then using physical clues found at that location coupled with the next clue from the box, determine where to go for the next step.
You could do one of the firefighting robot competitions. We built a robot in university for my bachelor's final project, but didn't have time to enter the competition. Plus the robot needed some polish anyway... :)
Video here.
Mind you, this was done with a Motorola HC12 and a C compiler, and most components outside the microcontroller board were made from scratch, so it took longer than it should. Should be much easier with prefab components.
Path finding/obstacle navigation is typically a good project to start with. If you want something practical, take a look at how iRobot vacuums the floor and come up with a better scheme.
Depends on your background and if you want practical or cool. On the practical side, a remote control could be a simple starting point. It's got buttons and lights but isn't too demanding.
For a cool project maybe a Simon-style memory game or anything with lights & noises (thinking theremin-style).
I don't have suggestions or perhaps something like a line follower robot. I could help you with some links for inspiration
Arduino tutorials
Top 40 Arduino Projects of the Web
20 Unbelievable Arduino Projects
I'm currently developing plans to automate my 30 year old model train layout.
A POV device could be fun to build (just google for POV Arduino). POV means persistence of vision.
As a hobby project to keep myself out of trouble, I'd like to build a little programmer timer device. It will basically accept a program which is a list of times and then count down from each time.
I'd like to use a C or Java micro controller. I have used BASIC in the past to make a little autonomous robot, so this time around I'd like something different.
What micro controller and display would you recommend? I am looking to keep it simple, so the program would be loaded into memory via computer (serial is ok, but USB would make it easier)
Just use a PIC like 16F84 or 16F877 for this. It is more than enough.
As LCD use a 16 x 2 LCD. It is easy to use + will give a nice look to your project.
LCD
The language is not a matter. You can use PIC C, Micro C or any thing you like. The LCD's interface is really easy to drive.
As other components you will just need the crystal and 2 capacitors as oscillator + pull up resister. The rest of the components depend on the input method that you are going to use to set the times.
If you are using a computer to load the list then you will need additional circuit to change the protocols. Use MAX 232 to do that. If you want to use USB, you need to go ahead and use a PIC with USB support. (18F series)
(source: sodoityourself.com)
This is a set of nice tutorials you can use. You can purchase the products from them as well. I purchased once from them.
I would go with the msp430. An ez430 is $20 and you can get them at digikey or from ti directly, then sets of 3 microcontroller boards for $10 after that. llvm and gcc (and binutils) compiler support. Super simple to program, extremely small and extremely low power.
There are many ways to do this, and a number of people have already given pretty good suggestions AVR or PIC are good starting points for a microcontroller to work with that doesn't require too much in the way of complicated setup (hardware & software) or expense (these micros are very cheap). Honestly I'm somewhat surprised that nobody has mentioned Arduino here yet, which happens to have the advantage of being pretty easy to get started with, provides a USB connection (USB->Serial, really), and if you don't like the board that the ATMega MCU is plugged into, you can later plug it in wherever you might want it. Also, while the provided programming environment provides some high level tools to easily protype things you're still free to tweak the registers on the device and write any C code you might want to run on it.
As for an LCD display to use, I would recommend looking for anything that's either based on an HD44780 or emulates the behavior of one. These will typically use a set of parallel lines for talking to the display, but there are tons code examples for interfacing with these. In Arduino's case, you can find examples for this type of display, and many others, on the Arduino Playground here: http://www.arduino.cc/playground/Code/LCD
As far as a clock is concerned, you can use the built-in clock that many 8-bit micros these days provide, although they're not always ideal in terms of precision. You can find an example for Arduino on doing this sort of thing here: http://www.arduino.cc/playground/Code/DateTime. If you want something that might be a little more precise you can get a DS1307 (Arduino example: http://www.arduino.cc/cgi-bin/yabb2/YaBB.pl?num=1191209057/0).
I don't necessarily mean to ram you towards an Arduino, since there are a huge number of ways to do this sort of thing. Lately I've been working with 32-bit ARM micros (don't do that route first, much steeper learning curve, but they have many benefits) and I might use something in that ecosystem these days, but the Arduino is easy to recommend because it's relatively inexpensive, there's a large community of people out there using it, and chances are you can find a code example for at least part of what you're trying to do. When you need something that has more horsepower, configuration options, or RAM, there are options out there.
Here are a few places where you can find some neat hardware (Arduino-related and otherwise) for projects like the one you're describing:
SparkFun Electronics
Adafruit Industries
DigiKey (this is a general electronics supplier, they have a bit of everything)
There are certainly tons more, though :-)
I agree with the other answers about using a PIC.
The PIC16F family does have C compilers available, though it is not ideally suited for C code. If performance is an issue, the 18F family would be better.
Note also that some PICs have internal RC oscillators. These aren't as precise as external crystals, but if that doesn't matter, then it's one less component (or three with its capacitors) to put on your board.
Microchip's ICD PIC programmer (for downloading and debugging your PIC software) plugs into the PC's USB port, and connects to the microcontroller via an RJ-11 connector.
Separately, if you want the software on the microcontroller to send data to the PC (e.g. to print messages in HyperTerminal), you can use a USB to RS232/TTL converter. One end goes into your PC's USB socket, and appears as a normal serial port; the other comes out to 5 V or 3.3 V signals that can be connected directly to your processor's UART, with no level-shifting required.
We've used TTL-232R-3V3 from FDTI Chip, which works perfectly for this kind of application.
There are several ways to do this, and there is a lot of information on the net. If you are going to use micro controllers then you might need to invest in some programming equipment for them. This won't cost you much though.
Simplest way is to use the sinus wave from the power grid. In Europe the AC power has a frequency of 50Hz, and you can use that as the basis for your clock signal.
I've used Atmel's ATtiny and ATmega, which are great for programming simple and advanced projects. You can program it with C or Assembly, there are lots of great projects for it on the net, and the programmers available are very cheap.
Here is a project I found by Googling AVR 7 segment clock.
A second vote for PIC. Also, I recommend the magazine Circuit Cellar Ink. Some technical bookstores carry it, or you can subscribe: http://www.circellar.com/
PIC series will be good, since you are creating a timer, I recommend C or Assembly (Assembly is good), and use MPLAB as the development environment. You can check how accurate your timer with 'Stopwatch' in MPLAB. Also PIC16F877 has built in Hardware Serial Port. Also PIC16F628 has a built in Hardware serial port. But PIC16F877 has more ports. For more accurate timers, using higher frequency oscillators is recommended.