Is there any stack that can be an alternative for the Microchip ZigBee Stack? I have a PIC18F27J53 microcontroller and MRF24J40MB Transceiver. I tried to read and understand the examples included in the Microchip ZigBee Stack but I have no luck. I think the examples are too complex for beginners like me. I only intend to send and receive data to and from sensor nodes. Also, PIC18F27J53 is not included in the Zena Configuration Tool device list.
Any help will be much appreciated.
1.You can try cc2500 rf pro. Its easier, cleaner and quite inexpensive than ZigBee.
2. OR even better you can try to use ZigBee with the arduino. You have inbuilt libraries, and if you say you are a beginner, then sending data will be as easy as writing to the UART port, which is by the way a one line command. 3. OR if you dont mind lower frequencies you can go for the standard rf module (or so it is called). You can find more about it, and how to use it here. http://extremeelectronics.co.in/rf/rf-communication-between-microcontrollers-part-i/
I would go for Option 2 first, then 3 then 1. (since you said that you are a beginner).
Related
I've an issue with my current micropython project on my ESP8266. I've a 10x10 LED matrix which i would like to control via 4 shift registers.
In general 3 pins are required for the controlling DATA, LATCH and CLOCK. After some hours of internet searching the most promising solution was the usage of SPI, where also found some useful instructions for the pyboard (thank you for the code btw):
https://forum.micropython.org/viewtopic.php?t=1219
I tried to replace the pyboard specific librarys with the general machine module for the ESP8266 to get access to the SPI class. It worked fine till a specific point but the main issue at the moment is that it was not capable provide a binary signal at the DATA pin.
To be honest I'm a little bit confused about the write methods in the machine.SPI class. The docu says the return value is None. So in general what is the purpose of a write method with a return value of None (sry for the maybe silly question)
Is there maybe another solution to get a binary signal out of the data pin? I'm not sure anymore if the usage of SPI is the best way to manage the controlling. Do you have some other examples or tutorials to get deeper into the topic?
Thank you for your kind response in advance,
BR charlzo
I need to implement a software module that is able to retrieve the topology of an autonomous system.
Looking at the various protocol that are implemented in Cisco routers i concluded that the only two alternatives to obtain topology are smnp and ospf.
The first one is a workaround and i don't want to use it, this leads to ospf.
I haven't found library in c, java and python that are usable; this one ( http://www.ospf.org/ )is probably the most complete but comes without documentation and i don't have enough time to analyze all the code.
So i found quagga that can implement a software ospf router; seems the perfect alternative since it can work with both real network and simulated network in gns3.
But it's possible to obtain the ospf routing table from quagga since everything is from command line?
This are my conclusions and doubts if someone can suggest something better or help me with the next step it would be appreciated since i'm stuck at the moment.
Use quagga's ospfclient feature. There is already an example provided in the ospfclient directory (see ospfclient.c) which will show you how to retrieve the LSA database from a quagga/ospfd instance. For this solution to work you need to attach a PC to one of your OSPF backbone routers and configure quagga/ospfd on it to successfully learn the routes then you start your ospfclient to retrieve any information you need.
I'm nxj beginner.
I have some questions about bluetooth communication between PC and brick.
First, when bluetooth communication occurs, where is the birthplace processing this datas?
In other words, I want to know whether these datas will be processed on CPU or brick.
Second, what is exact roles CPU and brick in bluethooth communication?
That means what is processed on CPU and what is processed on brick.
I have searched almost web site but I can't find this anywhere.
Please help me. Thanks.
You can see it in the package structure.
lejos.nxt.*
This package contains classes running on the NXT-brick. All code in this package will be compiled for the brick and will run on the brick.
lejos.pc.*
Here the difference is not that clear. This is java-code you compile for personal computer. So most code runs on your computer. But some classes (e.g: RemoteMotorController) only send messages to the NXT-brick which gives commands to the motors.
lejos.pc.comm provides API's that allow you to communicate/control the nxt robot from the PC.
When importing the the libs to an Android project, it allows you to build an instance of the same environment used on a pc, but within android.
I agree it can be tough finding some things out. It would be great if there was as stronger lejos presence on SO
This question is months old and has remained un-answered I actually have a lot of questions about it myself, but I might be able to provide some insight for utter novices.
when using bluetooth with Android and NXJ robots, you use either lejos.pc.comm or lejos.NXJ.
Both provide APi's to do almost the same thing, but work a little differently. I don't know nearly enough about the NXJ api, but I do know that it is the one that lets you manipulate the robot much more effectively, such as outputting data to it's LCD screen, which you can't do with the pc.comm api
As far as I can tell, the pc.comm API uses both Android Bluetooth API's and it's own protocols to allow communication with Lego LCP commands.
(I want to come back to this, but I'm writing a dissert on the topic so I'll try to update it in a couple of days. Seems not many are interested though, shame)
Is it possible to get location data out of Google Gears, Google Gelocation API or any other web location API (such as Fire Eagle) in such a format that it appears to other software as a GPS device?
It occured to me reading these answers to my question regarding WiFi location finding, on Super User, that if I could emulate a GPS unit, many of these web services could act as a 'poor-mans' GPS to otherwise less useful software that requires it.
Is GPSD an option?
Preferably OSX & Python, but I would be interested in any implementation.
There is a very similar thread on a Python mailinglist that mentions Windows virtual COM ports and discusses Unix's pseudo-tty capabilities. If the app(s) you want to use let you type in a specific tty device file, this may be the easiest route. (Short of asking the authors to provide a plugin API for what you're trying to do, or buying yourself a $20 bluetooth GPS mouse.)
Are you using OS X?
There is a project macosxvirtualserialport on Google code that provides a graphical wrapper around some of the features of a utility called socat. I'd recommend taking a look at socat if you see potential in the pseudo-tty route. I believe you could use socat to link a pipe from a Python program to a pseudo-tty.
Most native Mac apps will be querying IOServiceMatching for a device with kIOSerialBSDRS232Type, and I doubt that a pseudo-tty will show up as an IOKit service.
In this case, unless you can find a project that has already implemented such a thing, you will need to implement a driver as described in this How to create virtual COM port thread. If you're going to the trouble of create a device driver, you would want to base it on IOKit because of that likely IOServiceMatching query. You can find the Apple16X50Serial project mentioned in that post at the top of Apple's open source code list (go to the main page and pick an older OS release if you want to target something pre-10.6).
If your app is most useful with realtime data (e.g. the RouteBuddy app mentioned in the Python mailinglist thread can log current positions) then you will want to fetch updates from your web sources (hopefully they support long-polling) and convert them to basic NMEA RMC sentences. You do not want to do this from inside your driver code. Instead, divide your work up into kernel-land and user-land pieces that can communicate, and put as little of the code as possible into the kernel part.
If you want to let apps both read and write to these web services, your best bet would probably be to simulate a Garmin device. Garmin has more-or-less documented their protocol in the IntfSpec.pdf file included with their Device Interface SDK. Again, you'd want to split as much as you could into user-space code.
I was unable to find a project or utility that implements the kernel side of an IOKit-based virtual serial interface, but I'd be surprised if there wasn't one hiding somewhere out there. Unfortunately, most of the answers I found to that question were like this, with the developer being told to get busy writing a kext.
I'm not exactly sure how to accomplish what you're asking, but I may be able to lend some insight as to how you might begin to get it done. So here goes:
A GPS device shows up to most systems as nothing more than a serial device -- a.k.a. a COM port if you're dealing with Windows, /dev/ttySx if you're in *nix. By definition, a serial port's specific duty is to stream data across a bus, one block at a time. So, it would then follow logically that if you want to emulate the presence of a GPS device, you should gather the data you're consuming and put it into a stream that somehow acts like an active serial port.
There are, however, some complications you might want to consider:
Most GPS devices don't just send out location data; there's also information on satellite locations, fix quality, bearing, and so on. Then again, nobody's made any rules saying you have to make all that data available. There's probably more to this, but I'll admit that I need to do more research in this area myself.
I'm not sure how fast you can receive data when dealing with Google Latitude, etc., but any delays in receiving would definitely result in visible pauses in your "serial port"'s data stream. Again, this may not be as big a complication as it seems, because GPS devices are known to "burst" data across the bus anyway, but I'd definitely keep an eye on that. You want to make sure there's always a surplus of data coming across, not a shortage.
Along the way you'll also have to transform the coordinates you receive into valid GPS sentences, as well. You can find specifications for those, but I would definitely make friends with the NMEA standard -- even though it is a flawed standard, it's the one everyone seems to agree on anyway.
Hope this helped you, at least a little bit. Are there anymore details specific to your problem that you think could be useful in answering this question?
Take a look to Franson GPS Gate which allows you to connect to Google Earth among other things (like simulating GPS and so on). Is windows only though but I think you could get some useful ideas from it.
I haven't looked into it very much, but have you considered using Skyhook's SDK? It might provide you with some of what you are looking for. It's available for every major desktop and mobile OS.
Where would you recommend that I find a company to develop or buy a CD/DVD loading arm similar to: http://www.dextimus.com/
Preferably programmable via USB but if I only can get one with a serial interface that would be fine. Drivers dont matter - I can interface directly with the unit as my situation is very unique.
If you have some experience with electronics, you can give it a shot and build it yourself, like this or this.
I should add that the schematics and the source code are included, and in more details in the first project.
I suppose I might just shorten this by giving a list of resources first:
http://www.embedinc.com/ I trust this company to do good work. Expensive (actually, they are reasonably priced in the design community, but would be considered expensive by most hobbyists and individuals). Not great at people skills, but very very very good at what they do.
You should check out the various microcontroller communities and forums for hobbyists and professionals that can do this. Search for microchip, atmel, msp430, arm, powerpc, etc.
Sparkfun is a supplier to the electronics community - they have great forums where you can post your request, and you'll find people who might do it for fun with only the cost of materials. Might take longer, might not be as 'professional' or well packaged and delivered, but it might be your best low cost option.
There are many electronic design companies that could do this (for instance, I can do this sort of thing).
But there are many questions you haven't answered (and may not have researched) that could prevent success:
Is this patented?
What CD loading/unloading methods are not patented, are out of patent, or otherwise available?
What is your design goal - a one off just for you, or a device that can be built in the hundreds for industrial use, or a device meant for general office workers/consumers that is built in the millions?
Do you realize that this design qould surely cost mroe than simply buying one, if one is all you need?
As an example, assuming you don't need the nice enclosure and don't mind a 'prototype' look, just the mechanicals, electronics, and firmware design (no software on the PC) would likely be 100-250 billable hours for a design firm. At a cheap $90/hr, that's $9k to nearly $25k for one prototype. Add PC software and the nice enclosure, etc and you'll double that.
If you can find a local 'Make' group (techshop, GoTech, or similar) then you might be able to find a hobbyist that is willing to play with this idea for the cost of materials.
But if you define what your goal is, and give us an idea of your resources you may find a better answer.
-Adam
You can create a very nice simple solution using radio control servos. They come in many sizes, but even the small ones have enough torque to move a big arm to move a cd.
The real bonus with servos is that they normally have 180 degrees of rotation and internally have a variable resistor (rheostat) for positioning feedback. Positioning accuracy is normally within 1 degree of rotation which should be fine for a cd loader.
For picking up the CDs, nothing will beat a vacuum. I recommend a small battery powered vacuum cleaner. Funnel the suction into a 1/4 inch pipe. At the other end of the pipe a one inch diameter cup should provide more than enough lift from the small amount of suction.
As for the pile of blank CDs to be burnt, I would advise in moving the pile up rather than an arm down to it. probably having the top blank cd about 1/4 inch higher than the cd tray - By doing this, the arm only needs to rotate in one axis and the vacuum should be enough to suck the cd back out of the tray.
Now, for the electronics. For the servo control I suggest an rs232 serial servo controller. I've used the one from http://www.basicx.com/Products/servo/servo8t.htm as it also gives back torque information from the current draw.
For the low sample rate digital i/o, i suggest (for windows) inpout32.dll which is a dll to give you direct access to the bits of a parallel port. This will allow you to turn on the vacuum at the correct time and possibly sense when cd's have run out. Note that a parallel port can sink more current than it sources so for outputs you should connect to the 5v power line and set the output pin to 0 to turn on the output and 1 to turn it off.
The other nice option, which is very, very simple to interface and very cheap is to get hold of a picaxe from http://www.rev-ed.co.uk/picaxe/. These use a very simple programming language (a BASIC spin off) allowing you to read serial data in and control the servos and digital I/O on one chip. Last time I used one, the language was a bit simple - if statements had to jumped labels, else didn't exist.
If you do use a microcontroller and servos, it is best to use a dual voltage power supply as servos are noisy and can cause the microcontrollers to reset.
As for switching loads such as the vacuum on, you'll need to use a mosfet or (if money is no object) the simpler option, a solid state relay.
All digital inputs you use on the microcontroller should be pulled either to +V or ground with say a 5k resistor so they never float.
I cannot stress how simple and cheap the picaxes are. They have a built in interpreter so although code space is minimal on the small 8 pin units, they are programmable via a simple serial lead.
Good luck. Once you get into automation control, you'll never be able to stop. I'm in the middle of building a 3 axis CNC router so I can cut parts for other projects (I tell my girlfriend it's so she can cut out xmas decorations!).
You might want to contact Aaron Shephard about his Florian project.
I've found that a really easy board to control stepper motors or sorvos are produced by phidgets - the API is incredibly easy, and available for a vast array of platforms.