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A complete novice is here seeking some help regarding MCU. The thing is that I want to develop a project which will help foster my learning of MCU but currently I am at Level (minus) 10. I have many questions regarding MCU becaue of having little to no experience with those. Since I am inclined towards 8051 variants, my questions will be around that itself. I'll list the questions in pointer form here.
What is the main point of difference between a development board/lit or prototyping board? Can I program/burn an MCU if I have one of these or do I need a separate piece of hardware called programmer to put the hex code onto the MCU?
What is the difference between the programming of AT89c2051 and ATs52? Which one of the two can I program using the USB port on my laptop without much cost on the additional hardware? I was suggested to use 89v51rd2 because it can be programmed with just MAX232 without the use of any programmer however the additional cost of this MCU prevents me from going for it. I'd rather buy or build a programmer for myself and use 89c2051. But the problem is that I don't know how to program this thing using the USB port on my laptop.
Please guide.
Thanks
this ticket should get closed since it is not a programming question, primarily opinion based and/or just go read the manual are main reasons.
First off...just go read the manual. the 8051 is still alive and well but I wouldnt go there as your first mcu. There are avr based and msp430 based and arm based (and pics, my first but least favorite). The 8051 and arm based are going to be built by many different chip vendors in many different flavors. So as far as programming/burning your program into it, it can vary per vendor or chip family per vendor or per chip, basically there is on one answer. and you will find that some chips have more than one solution.
You wont need a max232. From usb, that is likely a waste, because you need to get from usb to rs232 levels then the max232 takes you back down to the chips I/O levels (unless your chip is a hybrid and has RS232 levels). they generally if not always use the normal gpio levels for the uart. what you are looking for is something ftdi based ft2232 or one of the many variants. can get cables now with the ftdi part in them or breakout boards $15 or less (plus stuff to hook it up, pins, jumper wires, whatever).
the arduinos are avr based and are getting cheaper and are massively popular tons of examples and users out there to help. st has a number of nice cortex-m based boards for $10 to $20 (nucleo, stm32 f0 discovery, f4 discovery). ti.com/launchpad has a number of boards msp430 and arm based (and their old dsp line if interested) for similar prices. Sometimes, seems like annually they lower the entry level msp430 board to $4.30. used to be free shipping but now there is a fairly reasonable shipping cost.
Basically you have to just do your reasearch, the information is all out there, some companies docs are better than others, some products have better online communities or examples or whatever than others. Then there is the processor type which may or may not matter to you, tools (this day and age the tools should be free, if not move on), libraries if you want to use canned ones or roll your own, etc...It can be overwhelming, perhaps just take the part that you specified, and read more about it, what the programming interface is. Being atmel their docs are usually pretty good at least for avr and arm based processors but perhaps for their 8051's as well.
I'm in the processes of buying a new data acquisition system for my company to use for various projects. At first, it's primary purpose will be to monitor up to 20 thermocouples and control the temperature of a composites oven. However, I also plan on using it to monitor accelerometers, strain gauges, and to act as a signal generator.
I probably won't be the only one to use it, but I have a good bit of programming experience with Atmel microcontrollers (C). I've used LabVIEW before, but ~5 years ago. LabVIEW would be good because it is easy to pick up on for both me and my coworkers. On the flip side, it's expensive. Right now I have a NI CompactDAQ system with 2 voltage and one thermocouple cards + LabVIEW speced out and it's going to cost $5779!
I'm going to try to get the same I/O capabilities with different NI hardware for less $ + LabVIEW to see if I can get it for less $. I'd like to see if anyone has any suggestions other than LabVIEW for me.
Thanks in advance!
Welcome to test and measurement. It's pretty expensive for pre-built stuff, but you trade money for time.
You might check out the somewhat less expensive Agilent 34970A (and associated cards). It's a great workhorse for different kinds of sensing, and, if I recall correctly, it comes with some basic software.
For simple temperature control, you might consider a PID controller (Watlow or Omega used to be the brands, but it's been a few years since I've looked at them).
You also might look into the low-cost usb solutions from NI. The channel count is lower, but they're fairly inexpensive. They do still require software of some type, though.
There are also a fair number of good smaller companies (like Hytek Automation) that produce some types of measurement and control devices or sub-assemblies, but YMMV.
There's a lot of misconception about what will and will not work with LabView and what you do and do not need to build a decent system with it.
First off, as others have said, test and measurement is expensive. Regardless of what you end up doing, the system you describe IS going to cost thousands to build.
Second, you don't NEED to use NI hardware with LabView. For thermocouples your best bet is to look into multichannel or multiple single-channel thermocouple units - something that reads from a thermocouple and outputs to something like RS-232, etc. The OMEGABUS Digital Transmitters are an example, but many others exist.
In this way, you need only a breakout card with lots of RS-232 ports and you can grow your system as it needs it. You can still use labview to acquire the data via RS-232 and then display, log, process, etc, it however you like.
Third party signal generators would also work, for example. You can pick up good ones (with GPIB connection) reasonably cheaply and with a GPIB board can integrate it into LabView as well. This if you want something like a function generator, of course (duty cycled pulses, standard sine/triangle/ramp functions, etc). If you're talking about arbitrary signal generation then this remains a reasonably expensive thing to do (if $5000 is our goalpost for "expensive").
This also hinges on what you're needing the signal generation for - if you're thinking for control signals then, again, there may be cheaper and more robust opitons available. For temperature control, for example, separate hardware PID controllers are probably the best bet. This also takes care of your thermocouple problem since PID controllers will typically accept thermocouple inputs as well. In this way you only need one interface (RS-232, for example) to the external PID controller and you have total access in LabView to temperature readings as well as the ability to control setpoints and PID parameters in one unit.
Perhaps if you could elaborate on not just the system components as you've planned them at present, but the ultimaty system functionality, it may be easier to suggest alternatives - not simply alternative hardware, but alternative system design altogether.
edit :
Have a look at Omega CNi8C22-C24 and CNiS8C24-C24 units -> these are temperature and strain DIN PID units which will take inputs from your thermocouples and strain gauges, process the inputs into proper measurements, and communicate with LabView (or anything else) via RS-232.
This isn't necessarily a software answer, but if you want low cost data aquisition, you might want to look at the labjack. It's basically a microcontroller & usb interface wrapped in a nice box (like an arduino (Atmel AVR + USB-Serial converter) but closed source) with a lot of drivers and functions for various languages, including labview.
Reading a thermocouple can be tough because microvolts are significant, so you either need a high resolution A/D or an amplifier on the input. I think NI may sell a specialized digitizer for thermocouple readings, but again you'll pay.
As far as the software answer, labview will work nicely with almost any hardware you choose -- e.g. I built my own temperature controller based on an arduino (with an AD7780) wrote a little interface using serial commands and then talked with it using labview. But if you're willing to pay a premium for a guaranteed to work out of the box solution, you can't go wrong with labview and an NI part.
LabWindows CVI is NI's C IDE, with good integration with their instrument libraries and drivers. If you're willing to write C code, maybe you could get by with the base version of LabWindows CVI, versus having to buy a higher-end LabView version that has the functionality you need. LabWindows CVI and LabView are priced identically for the base versions, so
that may not be much of an advantage.
Given the range of measurement types you plan to make and the fact that you want colleagues to be able to use this, I would suggest LabVIEW is a good choice - it will support everything you want to do and make it straightforward to put a decent GUI on it. Assuming you're on Windows then the base package should be adequate and if you want to build stand-alone applications, either to deploy on other PCs or to make a particular setup as simple as possible for your colleagues, you can buy the application builder separately later.
As for the DAQ hardware, you can certainly save money - e.g. Measurement Computing have a low cost 8-channel USB thermocouple input device - but that may cost you in setup time or be less robust to repeated changes in your hardware configuration for different tests.
I've got a bit of experience with LabView stuff, and if you can afford it, it's awesome (and useful for a lot of different applications).
However, if your applications are simple you might actually be able to hack together something with one or two arduino's here, it's OSS, and has some good cheap hardware boards.
LabView really comes into its own with real time applications or RAD (because GUI dev is super easy), so if all you're doing is running a couple of thermopiles I'd find something cheaper.
A few thousand dollars is not a lot of money for process monitoring and control systems. If you do a cost/benefit analysis, you will very quickly recover your development costs if the scope of the system is right and if it does the job it is intended to do.
Another tool to consider is National Instruments measurement studio with VB .NET. This way you can still use the NI hardware if you want and can still build nice gui's quickly.
Alternatively, as others have said, it is perfectly viable to get industrial serial based instruments and talk to them with LabVIEW, VB .NET, c# or whatever you like.
If you go down the route of serial instruments, another piece of hardware that might be useful is a serial terminal (example). These allow you to connect arbitrary numbers of devices to your network. You computers can then use them as though they were physical COM ports.
Have you looked at MATLAB. They have a toolbox called Data Acquisition. compactDAQ is a supported hardware.
LabVIEW is a great visual programming environment. In terms if we want to drag,drop and visualize our system. NI Hardware also comes with the NIDAQmx Library which can be accessed through our code. Probably a feasible solution for you would be to import the libraries into another programming language and write code for all the activities which otherwise you were going to perform using LabVIEW. Though other overheads like code optimization would be the users responsibility, you are free to tweak the normal method flow, by introducing your own improvements at suitable junctures in the DAQ process.
I am new to the locating hardware side of embedded programming and so after being completely overwhelmed with all the choices out there (pc104, custom boards, a zillion option for each board, volume discounts, devel kits, ahhh!!) I am asking here for some direction.
Basically, I must find a new motherboard and (most likely) re-implement the program logic. Rewriting this in C/C++/Java/C#/Pascal/BASIC is not a problem for me. so my real problem is finding the hardware. This motherboard will have several other devices attached to it. Here is a summary of what I need to do:
Required:
2 RS232 serial ports (one used all the time for primary UI, the second one not continuous)
1 modem (9600+ baud ok) [Modem will be in simultaneous use with only one of the serial port devices, so interrupt sharing with one serial port is OK, but not both]
Minimum permanent/long term storage: Whatever O/S requires + 1 MB (executable) + 512 KB (Data files)
RAM: Minimal, whatever the O/S requires plus maybe 1MB for executable.
Nice to have:
USB port(s)
Ethernet network port
Wireless network
Implementation languages (any O/S I will adapt to):
First choice Java/C# (Mono ok)
Second choice is C/Pascal
Third is BASIC
Ok, given all this, I am having a lot of trouble finding hardware that will support this that is low in cost. Every manufacturer site I visit has a lot of options, and it's difficult to see if their offering will even satisfy my must-have requirements (for example they sometimes list 3 "serial ports", but it appears that only one of the three is RS232, for example, and don't mention what the other two are). The #1 constraint is cost, #2 is size.
Can anyone help me with this? This little task has left me thinking I should have gone for EE and not CS :-).
EDIT: A bit of background: This is a system currently in production, but the original programmer passed away, and the current hardware manufacturer cannot find hardware to run the (currently) DOS system, so I need to reimplement this in a modern platform. I can only change the programming and the motherboard hardware.
I suggest buying a cheap Atom Mini-ITX board, some of which come with multi - 4+ RS232 ports.
But with Serial->USB converters, this isn't really an issue. Just get an Atom. And if you have code, port your software to Linux.
Here is a link to a Jetway Mini-Itx board, and a link to a 4 port RS232 expansion module for it. ~$170 total, some extra for memory, a disk, and a case and PSU. $250-$300 total.
Now here is an Intel Atom Board at $69 to which you could add flash storage instead of drives, and USB-serial converters for any data collection you need to do.
PC104 has a lot of value in maximizing the space used in 19" or 23" rackmount configurations - if you're not in that space, PC104 is a waste of your time and money, IMHO.
The BeagleBoard should have everything you need for $200 or so - it can run Linux so use whatever programming language you like.
A 'modern' system will run DOS so long as it is x86, I suggest that you look at an industrial PC board from a supplier such as Advantech, your existing system may well run unchanged if it adheres to PC/DOS/BIOS standards.
That said if your original system runs on DOS, the chances are that you do not need the horsepower of a modern x86 system, and can save money by using a microcontroller board using something fairly ubiquitous such as an ARM. Also if DOS was the OS, then you most likely do not need an OS at all, and could develop the system "bare-metal". The resources necessary just to support Linux are probably far greater than your existing application and OS together, and for little or no benefit unless you intend on extending the capability of the system considerably.
There are a number of resources available (free and commercial) for implementing a file system and USB on a bare-metal system or a system using a simple real-time kernel such as FreeRTOS or eCOS which have far smaller footprints than Linux.
The Windows embedded site ( http://www.microsoft.com/windowsembedded/en-us/default.mspx )
has a lot of resources and links to hardware partners, distributors and development kits. There's even a "Spark" incubation project ( http://www.microsoft.com/windowsembedded/en-us/community/spark/default.mspx )
What's also really nice about using windows ce is that it now supports Silverlight as a development environment.
I've used the jetway boards / daughter cards that Chris mentioned with success for various projects from embedded control, my home router, my HTPC front end.
You didn't mention what the actual application was but if you need something more industrial due to temperature or moisture constraints i've found http://www.logicsupply.com/ to be a good resource for mini-itx systems that can take a beating.
A tip for these board is that given your minimal storage requirements, don't use a hard drive. Use an IDE adapter for a compact flash card as the system storage or an SD card. No moving parts is usually a big plus in these applications. They also usually offer models with DC power input so you can use a laptop like or wall wart external supply which minimizes its final size.
This http://www.fit-pc.com/web/ is another option in the very small atom PC market, you'd likely need to use some USB converters to get to your desired connectivity.
The beagle board Paul mentioned is also a good choice, there are daughter cards for that as well that will add whatever ports you need and it has an on board SD card reader for whatever storage you need. This is also a substantially lower power option vs the atom systems.
There are a ton of single board computers that would fit your needs. When searching you'll normally find that they don't keep many interface connectors on the processor board itself but rather you need to look at the stackable daughter cards they offer which would provide whatever connections you need (RS-232, etc.). This is often why you see just "serial port" in the description as the final physical layer for the serial port will be defined on the daughter card.
There are a ton of arm based development boards you could also use, to many to list, these are similar to the beagle board. Googling for "System on module" is a good way to find many options. These again are usually a module with the processor/ram/flash on 1 card and then offer various carrier boards which the module plugs into which will provide the various forms of connectivity you need.
In terms of development, the atom boards will likely be the easiest if your more familiar with x86 development. ARM is strongly supported under linux though so there is little difficulty in getting these up and running.
Personally i would avoid windows for a headless design like your discussing, i rarely see a windows based embedded device that isn't just bad.
Take at look at one of the boards in the Arduino line, in particular the Arduino Mega. Very flexible boards at a low cost, and the Mega has enough I/O ports to do what you need it to do. There is no on-chip modem, but you can connect to something like a Phillips PCD3312C over the I2C connector or you can find an Arduino add-on board (called a "shield") to give you modem functionality (or Bluetooth, ethernet, etc etc). Also, these are very easy to connect to an external memory device (like a flash drive or an SD card) so you should have plenty of storage space.
For something more PC-like, look for an existing device that is powered by a VIA EPIA board. There are lot of devices out there that use these (set-top boxes, edge routers, network security devices etc) that you can buy and re-program. For example, I found a device that was supposed to be a network security device. It came with the EPIA board, RAM, a hard drive, and a power supply. All I had to do was format the hard drive, install Linux (Debian had all necessary drivers already included), and I had a complete mini-computer ready to go. It only cost me around $45 too (bought brand new, unopened on ebay).
Update: The particular device I found was an EdgeSecure i10 from Ingrian Networks.
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.
I know little about MCUs and embedded systems.
A year ago we made contract with a company to design a special purpuse MP4 device based on the SigmaTel STMP 3650 kit. Now we have all the source code for the firmware (code, resource around 1G).
My questions are
Can we use this code to run on other STMP 3xxx famliy based devices (with acceptable modification, of course)? What about other ARM9 based devices?
ARM9 defines the processor core (but even then there are variants; yours being ARM962EJ-S), but most on-chip peripherals and support hardware including clocks, PLLs, and interrupt controller are vendor specific, you you would have to port your hardware initialisation and device driver code, and make sure that you choose a device with a comparable peripherals set to the ones your current code uses.
Moreover if the code is written in C or C++ rather than assembler, much of it may be prtable to other architectures, particularly if the application layer and hardware abstraction layer are well defined.
Another issue may be whether your existing implementation relies on any particular OS or RTOS; you may need to select a device that supports the same OS in order to reduce the porting effort.
Finally, a non-programming point, but just to keep you out of trouble; you need to be sure that you own the rights to the code you intend to reuse, and that the original client has no claim on it.
your logical successor chip is iMX233 from Freescale for a couple of reasons.
STMP3650 lead to STMP3780 by SigmaTel - same CPU core (ARM9EJ-S), mostly same architecture and registers. Then, SigmaTel was sold to Freescale and they simply copied STMP3780 to ...iMX233. Identical silicon.
We have a fully fledged MP3/MP4 player based on STMP3650 (see bones.ch website) and transfer our R&D now to iMX233. What is your project doing by now? How "good" was the design based on STMP3650 running? Do you have any chip stock left?