Compactrio RS232 question

I have Compactrio 9074. How do I setup the rs232 port setting. I try to run"LabVIEW 2009\vi.lib\Instr\_visa.llb\VISA Configure Serial Port (Instr).vi" to setup the port I get a error. I would like to communicate over RS23 with the compactRIO.
Port name = RIO0::INSTR
error code = -1073807331
Error desciption
Error -1073807331 occurred at Property Node (arg 2) in VISA Configure Serial Port (Instr).vi
Possible reason(s):
VISA: (Hex 0xBFFF001D) The specified attribute is not defined or supported by the referenced resource.
Sam

I have written LabVIEW for serial communication. I have the Serial
software that communicates between the instrument and computer. I want to
run the RS232 communication software on the CompactRIO. I got everything
working on the CompactRIO but the RS232 port. The RS232 software is fine
because I can run it on a computer talking to the instrument.
LabVIEW has a RS232 configure serial Port. If I call out the wrong
port, I should and get an error. If I call out the correct port, I should
not get an error even if the instrument is not connected. All I'm doing
is trying to initialize the port configuration.
On the compactRIO, I have NI-RIO 3.2.0(minimal) installed. I'm trying
to initialize the baud rate before I talk to the instrument. Attached is
the init vi I'm using.
Thanks for the response
Sam
Attachments:
InitSerial.vi ‏11 KB

Similar Messages

Strange RS232 question

Hi,
I am supposed to read some data from the RS232 port and plot it on the waveform. The data looks like this: (ASCII Strings seperated by return)
134
343
12F
12
To test, I wrote a Labview program to send out this kind of data to the RS232 port. It is a for loop and for each loop step, it will translate the data into an ASCII string and send it to the RS232 port. For example, number 48 will be translated to "48".
I made a loopback on the RS232 port, and wrote another Labview program to read the RS232 data in, translate into numerical and plot on waveform. It is a while loop, for each loop step, it will check the bytes on the serial port, if it is bigger than 0, it will read the bytes and translate into number and plot it.
This works fine in loopback mode, it can capture every line of string and plot it perfectly.
But then I switched to the real environment, the data is sent by others, I checked the data by Hyperterminal and it is in accordance with the above format, but the strange thing is that now my receiving program got the data not line by line, instead, it got the data several lines per read. How can this be? And what can I do to make it read line by line while not losing other data? Not every sample data is of the same length.

By 'sync' I mean that the test app writes a few bytes, the receiver app reads a few bytes, etc. Since the two applications are running on the same machine they may be in sync timing-wise so that the reciever program happens to work as expected.
The serial port contains multiple buffers. For non-VISA it is a HW buffer and driver buffer. VISA may add an additional buffer.
When the computer receives a byte at a serial port, the serial driver grabs the byte from the hardware buffer and stores it in a software buffer. When you call Bytes at Serial Port, you're asking how many bytes are in the software buffer. Then you perform a read and get N bytes from the software buffer.
What I would do is make a routine that just reads from
the serial port and puts the resulting data in a buffer you define in LabVIEW (perhaps a queue of some sort?). Then your main program parses the buffer and processes the data accordingly.

Labview Real-Time and CompactRIO questions

Hi
everyone! We have new troubles about CompactRio and Real Time module:
-We want to
translate into real-time module a VI we have done with Labview 8 .2. In order
to do that we have discovered an option placed in Project Explorer (Tools->Real-Time
module->Communication Wizard) that seems to translate automatically into Real-Time
language. Is it true?
- If it was
true we would want to do a transmitter VI in CompactRio (RT target) and a receiver VI in the Host. But the
Communication Wizard creates a VI in the Host and a VI in the RT target (in
Real Time language) for each VI we enter to translate ( so we obtain 4 VI’s in
the same project , two of them as transmitter, and two of them as receiver)
-We have
tried to deploy some VI’s to the CompactRio and we get always an error.
CompactRio’s configuration is allright and it is well recognized by MAX. Why
does the error appear, and how can we work it out?
We
need to configure the Serial Port placed in CompactRio in order to adjust some
features, such us bauds value. MAX recognized the CompactRio’s Serial Port, but
all the opctions to configure them are disabled.
I hope you
can answer these questions. Thank you.
Ander

Hi again,
Still didn't find the problem on my side. Here's a picture of my code. If I put the code surrended in red at place (1), I don't get the error, but if I put the code at place (2), I get the error. Why oh why....?
I get the error when I close the browser or click Back button of the browser or Stop the application with the red dot or stop the application with the Quit button on my front panel.
This morning I found a post on this forum about getting an error using Property node and Remote panel (http://forums.ni.com/ni/board/message?board.id=170&message.id=252705). I did what they suggest: wire the property output to an indicator and it works (disable "Enable automatic error handling dialod" didn't work... I don't know why)... until I put extra code in my VI.
I really need help please!
Thank you
Stephanie
Attachments:
MemoryManager line 437 error.JPG ‏228 KB

New NI CompactRIO calls the question, "¿Quien is mas macho, Intel quad-core Atom or 4-year-old i7?"

Perhaps you remember the Saturday Night Live TV sketch from 1979 where Bill Murray played a game show host who asked the show’s titular question, “¿Quien es mas macho?”
Today, Matt Spexarth, Principal Product Manager for Embedded Systems at National Instruments (NI), called the NI CompactRIO controller introduced this week at NI Week—the model cRIO-9039, which pairs a 1.91GHz, quad-core Intel Atom CPU with a Xilinx Kintex-7 325T FPGA—the highest-performance CompactRIO ever released. That includes the existing cRIO-9082 controller, which pairs a 1.33GHz, dual-core Intel i7 CPU and a Xilinx Spartan-6 LX150 FPGA. So both the processor and the FPGA have been upgraded in the new CompactRIO controller. The NI cRIO-9039 controller es mas macho.
NI Model cRIO-9039 Controller in an 8-slot CompactRIO Chassis
The new NI CompactRIO controller runs security-enhanced NI Linux Real-Time. It has an SDHC card slot for non-volatile storage and can directly operate a local, graphical UI (user interface) as a human-machine interface. Another key performance feature, noted Spexarth, is a bank of DDR3 SDRAM attached directly to the Kintex-7 FPGA to allow the FPGA to directly handle large data sets, to process large FFTs for example.
As with the entire line of NI CompactRIO controllers, you program the cRIO-9039 controller using NI’s LabVIEW graphical development environment with its many add-on modules including LabVIEW FPGA. In addition, the new CompactRIO controller maintain compatibility with the many CompactRIO plug-in I/O hardware modules.

Whygirl,
it reads as though an internal disk upgrade (and possibly a battery replacement) would suffice for you, and those two together would be far less expensive than a new MacBook Pro. Yes, you could install either a HDD or a SSD in place of its current internal HDD. You could look at the Hitachi Travelstar 7K1000 as an example of a suitable 1 TB HDD; SSDs are more expensive per unit of storage than a HDD, but might be worth the extra cost if your apps are disk-bound. (I put a Samsung 840 PRO into my 13-inch Mid 2010 model, and it’s been working well.) Note that Chrome might be responsible for the extra heat (and the extra heat is responsible for the increased volume from the fans kicking in); Chrome isn’t optimized for use on 64-bit versions of OS X, like 10.8.5.

Basic questions for RS232/422/485 & Modbus

Hello,
i have to write some libraries for four types above.
But, i only have a normal windows-computer with a normal serial-connection.
Do i see it correct that can then only make "RS232" with this and that 422 amd 485 are then "special" serial-cards?
So for me it seems that 232/422/485 are three different hardware-types.
And only Modbus is a software-protocol that can be created with labview.
Is this correct?
Thanks for help
Solved!
Go to Solution.

RS232/422/485 are hardware specific. Many RS422 UART cards out there will also handle RS485. Luckily, most of these cards just show up as a COM port, so the software is the same for all 3.
According to Wikipedia, most Modbus devices use RS485 as the hardware layer. I will admit that I have no exprience with Modbus, so I'm not going to offer any advice on it.
There are only two ways to tell somebody thanks: Kudos and Marked Solutions
Unofficial Forum Rules and Guidelines

Compactrio usb wifi question

hi.
can i connect the compactrio to pc through the "usb wifi" ?
if yes, how should i do it ?
thz

其實跟 compactRIO 無關
就只是透過無線 Hub 讓電腦PC與 compactRIO 連線

Question about slow rs232 equipment

I tried the examples for rs232 communication, it works fine.
but my equipment is slow and needs delay between each character.
i didnt find any input to Visa write or other control which enables me
to do this.
can someone tell me how to do this?
again: to make a delay (inter digit pause) between each character send.
thanks in advance

A PIC for instance does not have a FIFO for its standard serial port module. You get a byte in a register and if you are not fast enough before the next byte is ready things might go wrong. Of course writing the PIC formware in such a way that it can always deal with the maximum input rate (for instance 9600 baud => ~1ms per byte) is the real art here.
Also you can consider handshaking too, although the PIC module does not have this automatically.
Rolf Kalbermatter
Rolf Kalbermatter
CIT Engineering Netherlands
a division of Test & Measurement Solutions

Design problem: RS232 communication

Hi,
I have a design problem for communication with a device via RS232. Since I'm normally a C++ programmer I might just look at the problem from a wrong angle and hope for some hints how to do it in LabVIEW.
The scenario:
A device is communicating with the PC via RS232. The device permanently sends data packets. At the same time, commands can be sent to the device and it returns replies. Data packets and reply packets are arbitrarily mixed, i.e. after sending a command there could be a couple of date packets before the reply comes back but the packets can be distinguished by an identifier.
At least one, ideally several VIs should communicate with the device. Commands should be sent by pressing buttons and the incoming data should be parsed (the packets contain mutliple data streams) and shown on graphs or saved to files.
My initial idea:
Coming from C++ I wanted to build a class for the communication that permanently reads the incoming data and splits it to reply and data packets. This class would then have a function to send out a command and would return the reply or a timeout and it would be possible to register and unregister listeners (I wanted to use queues for this) for the various data streams.
The problems I ran into:
There were a couple but the two most pressing problems were: how could I communicate with the constantly running sample VI (e.g. to stop sampling) and how could I propagate changes to the class to it (e.g. new listeners). Since it is not returning I don't see a good way to implement it as in instance funcion (i.e. pass it the object). I could probably not let the sample function run continously but call it periodically from outside. However I planned to implement the class as a singleton, so it could be used parallely from different VIs.
Is there a best practice for a case like this?
I'm glad about any hints or ideas.
Thanks,
Tobias

tfritz wrote:
Hi,
thanks. Since almost the same thing was suggested to me in a German forum I guess this is really common practice (using one VI with different methods controlled by a queue). It still seems a little "unnatural" for me but my biggest concern (bad interface description) was shattered by the suggestion in the link you sent me to wrap these functions with wrapper VIs, thus caller VIs won't have to deal with the call-by-queue-mechanism. This might also be easier to port to a different implementation later. However I still see the danger that the continously running VI could easily become bloated.
It also requires me to change the way I have looked at VIs until now. In our course they told us that VIs are basically functions. Using this design patterns, the VI becomes more of a module, really (Like a C module implemented in a C-Source file). But I will try it. It sounds as if it could work.
I will still look into the OOP solutions a little more, though. Do I understand you correctly that you wouldn't recommend using LVOOP because it's still buggy? What about dqGOOP for example? This sounds like it could do what I need (however it doesn't seem to implement things like polymorphism, late binding and inheritance so I don't quite see what's so OOP about it. It seems more like programming with structures in C.)
I don't know if LVOOP is buggy or not. I think early on it was buggy and things have improved in recent versions. I have read that it doesn't have all the features that you would have in OOP like C. I wouldn't recommend it only because I'm not familiar with it at all. I can't recommend something that I'm not comfortable with. If you go that route, plan on spending time in these forums and in LAVA to reading up on what others have done. I haven't hard of dqGOOP.
But back to your suggestion. I still have a couple of questions:
- How do you return values from the module? Would you use a queue for that as well?
- Where would the parameter queue be held (created and passed to the VI)
I would store all of these in a functional global variable. This is the VI that stores data in shift registers. Ben's action engine nugget is an advancement on that. This allows for both the calling VI and the parallel running subVI to get and set the data as needed. It runs quickly so neither process should be forced to wait while the other VI is doing its thing.
- My VI has to be constantly sampling and this shouldn't be interrupted too long by other functions as adding a listener. However both functionalities have to access the same kind of data. Is there an easy way to parallelize this? Would the sampling be a case in the case diagram that's always used if no command was sent to the VI or would it somehow run parallely? Yes. There are a couple of ways of doing this. One would be for the dequeue to have a timeout function. In the event the dequeue times out, you run the code that is doing the acquisition. I think a better method is that the code that does the acquisition enqueues its own command again to the end of the queue. Let's say that is command A. So when case A finishes, it enqueues A, which seeds itself to run again. So if nothing else comes into the queue, it just executes A , A, A, A. But let's say another section of code needs to do something such as command B. It will slip B into the queue while A is executing. So you would A, B, then A again, because A would get slipped back into the queue when the first A finishes, but B has already been put in while the first A was running.
- Would it be possible to make the VI reentrant and in this way use it simultaneously on different COM ports (using different parameter queues as well)? I'm not sure if I will need this but it would be neat if it could work.
I think you could do this. It may be a case where the VI is saved as a template (.vit) and you initiate it multiple times. I haven't needed to do this before, so I'm afraid I can't provide any details or useful tips.
Well, I will fool around some more. Thanks so much for your help. This is kind of exciting since the concepts are quite new for me. Btw, is there something like an academic theory (computer science) for LabVIEW? I came across functional languages in university but data flow languages are still a new concept for me.
Tobias
tfritz wrote:
Another question about the "dynamically starting" of the VI:
How is the path handled? Is it guaranteed that it always takes the VI from the project or does it just search for the first VI by that name it finds in the file structure? Does this still work when building an .exe from the project? What happens if the VI is already running? Can you test for this?
While I'm at it: is there a way to stop LabVIEW from searching for subVIs it can't find when openin a VI? This resulted in very unexpected behaviour sometimes where it would find the VI somewhere else (with the same name but maybe an older version).
In my case, I just had the path hardcoded. It is my only instance, I'm not planning on moving the VI's. If you don't have the path, it will take a VI by that name if it's in memory. If it isn't in memory, it starts searching relative to the calling VI's path. One thing I know, if you are dealing with relative paths, a subVI has a different relative path in an .exe as opposed to the development environment. The name of the .exe becomes a folder. So in development, if your sub VI is mySubVI.vi. In an executable, its path is MyExe.exe\MySubVI.vi
For all of this, I recommend searching the forums to get more details.
If it is searching for a VI, you can hit ignore. But of course you'd have to do it before it finds it. When you are dealing with versioning issues, I recommend making a backup copy of the entire directory structure elsewhere. Some location where it shouldn't stumble across it.

AT Commands over Bluetooth RS232 Connection

Hi all and thank you in advance.
I am trying hard to locate security related information about the following. If I establish an RS232 connection with a mobile phone through Bluetooth, is it possible then to utilize that connection to issue AT commands to the mobile phone in order to invoke the cellular modem? I have the impression that under MIDP such functionality is deliberately restricted for security reasons. Is this true?
PS.I know there are similar posts in the forum but non of them has been answered so I’m giving it a try.
Once again... thank you.

seanfisher, welcome to the forum. Please don't post in threads that are long dead. This question was asked 3½ years ago and it's hardly likely that Habib9, who hasn't visited these forums in the last 2½ years, is still waiting for an answer.
I'm locking this thread now and blocking your post.
db

Custom device / I am trying to use a vehicle controller model developed in LabVIEW with compactRIO (cRIO-9024)

Now I have developed a vehile controller model with LabVIEW so as to run on VxWorks operating system. ( compactRIO cRIO-9024)
And I converted a controller model of labview into *.lvmodel in order to use it as I did with simulink models.
However, converted *.lvmodel was not supported for VxWorks operating system. so after searching for this, I found out that I have to use a custom device.
I am now studying the custom device, but it looks diffcult because I dont have much experience in real-time system.
Here are my questions.
1. Simulation model in VeriStand
Should I convert a labview controller model into *.lvmodel even if I use the custom device in order to run on VxWorks operating system?
If not, what should I do after building a controller model with labview?
2. Operating system
It is silly question. anyway, as long as I run a controller model on compactRIO cRIO-9024, the operating system always has to be set to VxWorks. Is it right?
3. Custom device
This is the most difficult thing. I dont know even what to do. What functions should be inside a custom device template tool? The controller model send output signals to a vehicle model, and receive input signals from a vehicle model.
Thank you in advance.
Hognjun

Hi,
You should post this on the Veristand Forum.
http://forums.ni.com/t5/NI-VeriStand/bd-p/440
Ravi

Auto deploy a VI onto compactRIO or pop-up a vi on target in main VI

Hello
I have a main program where i have event structure and 2 state machines which do DAQ and Video. in a different project i have a pid controlled heater program that will be deployed on compactRIO. how do i program the main VI to auto deploy the heater program to target and get values from there to the main program. (for graph values can i use global varible between realtime program and normal main program)
I am thinking if i use the shared variable that is update by AI of a module on Compactrio in the main program, will it auto deploy it detecting that shared variables belong to target, but i want only the heater part of the program to get deployed not the event strucute, statemachines on the mian program. please help
If i can put a button on main program that when clicked can pop-up the heater program on compact RIO to adjust the PID parameters and close it and run with new values. is this possible?
Thanks in advance

Hi freemason,
I'm still a bit unclear on what you need. If you are able to develop your project such that all the VIs are located in thier respective locations (i.e. on the cRIO, RT or Windows Host), and you just want to change controls before running the FPGA vi, we can do that. Essentially, you use a read/write control VI before running the FPGA VI using the Run invoke node. You'll have to make sure to change the FPGA open reference options to not run the VI automatically (right click on it and select "Configure Open FPGA VI Reference...", uncheck the run option).
If you want to look at an example involving PID in the LabVIEW example finder, one that might be of particular interest is called "Template Multichannel PID". You can find this in through Help>Find Examples. Navigate to Hardware Input and Output>CompactRIO>FPGA Fundamentals>Analysis and Control.
You can use the execution of your host VI to start and stop the FPGA vi using the Read/Write Control VI and the Run invoke node. Also, you can use an invoke node to Abort the VI if that is necessary, but creating a stop control in the FPGA VI that allows the Host VI to stop using programming flow is usually more desirable.
I hope these suggestions help, but please clarify your question if you're still confused.
Also, Pablo. Try setting the VI to run as a start up application. A guide of how to do that is here.
Message Edited by Verne D on 04-06-2010 01:07 PM
Message Edited by Verne D on 04-06-2010 01:07 PM
Verne D. // LabVIEW & SignalExpress Product Support Engineer // National Instruments

GPIB and RS232 communication problems

I've been having several "interesting" problems with GPIB and RS232 communications in LabVIEW VIs. Some I'll mention at the end for curiosity, but right now I'm facing a rather big problem. I'm essentially self-taught at doing LabVIEW (using 8.5.1 right now), but by now I've had a lot of experience as their either has not been any drivers or pre-made VIs for the instruments I've needed or I've not been able to get the available drivers to work and had to write my own anyway (such as with the HP 3458A), but nothing seems to be working right now. I'm not at work, but we typically find forum sites blocked anyway (I can't even download the NI drivers at work since they house them on a ftp server, go figures) so I can't give the VI itself (it wouldn't be easy to get approval even if I could) so the best I can do right now is in words describe everything I've tried. I will be happy to post follow-ups of specific details if I can if they would be helpful.
I've been working on a routine to read data from an MKS 670 Signal Conditioner/Display with a MKS 274 Multiplexer with 3 connected MKS 690A Baratrons. Previously I've worked on programs using other older displays and the analog outputs which were being read by a DAQ card, but for a new project it was decided to try and just read the data directly. I first worked with a unit with just an RS232 Serial Port which I managed to get to work, but had so much problems with garbage readings and having to add checks and re-reads that by the end no matter what delays I added between each reading and how simplified the command routine down to just 2 sequences and the read that it took at least 10 seconds to get 1 reading from each channel.
Figuring maybe it was a limitation of the serial communications for these instruments I tried to re-work it for a unit with a GPIB port with which I'm actually much more familiar. The problem is that I cannot get anything at all from the unit through GPIB. Everything even the bare-bones built-in GPIB CLR function times out with no response from the instrument no matter how long I set the timeout limit and it also freezes the entire GPIB bus as well. It isn't a waiting issue as it freezes on the very first command. The GPIB initialization function seems to work (I typically find this to be unnecessary), but the instrument itself doesn't even respond with a status code. I've also tried just the basic GPIB write functions with even just passing the <cr> and <lf> characters as well. In Measurement and Automation Explorer most of the time the instrument won't even appear when doing search for instruments and when it does it shows as not responding to the *IDN? command (yes I've messed with the EOI, EOS, etc settings and I've even changed the GPIB address even though when it gets this far it confirms that I have the correct address) and even tried manually doing the *IDN?, *RST, and *CLR commands even with <cr> and <lf> characters which the manual for these units clearly states are compatible commands and NI SPY and everything show no response at all. I've tried 2 different GPIB units, 3 different computers including several that are not online and haven't been updated for a while, and using older LabVIEW versions, extensive re-booting and resetting of computers and devices and still nothing. I'm using an NI GPIB-USB-HS GPIB to USB adaptor which I've used extensively on other systems and even re-connected to those systems and everything worked fine. When I hooked up equipment that I knew was working, it would either freeze the entire GPIB bus until well past whatever timeout setting I set at which point all the instruments would appear, but none responding to *IDN? queries or nothing would appear at all, or if I manually turned it off when frozen the other instruments would work and most even respond to the *IDN? queries. The same goes for both of the GPIB instruments of this type that I tried and again for different versions of LabVIEW, difference computers (all Windows XP though), and every GPIB configuration setting I can find to mess with in every combination.
Any thoughts or suggestions would be greatly appreciated. I've had all sorts of weird problems with equipment and LabVIEW (you've got to love undocumented design features) that have frustrated me before, but I've never had an instrument never respond at all especially a GPIB one. Getting garbage yes, no response at all, no.
The side side issues I'm just mentioning as they may be related, but I'm really interested in the above as I have working solutions for these:
One I've had is with a Hart Scientific (prior to being bought by Fluke) 1560 Black Stack that would continually stop responding to GPIB commands when on a continual read function taking readings just every 4 seconds with 250ms between each GPIB read or write command but for up to hours in total and the times it stops responding are random as far as I can tell. I even started sending the *RST command before and after every read or write command and still it freezes. The only thing is to manually turn it off and then back on or manually go through the menus and manually trigger the GPIB reset routine at which point it immediately starts responding. However, when I got sick of having to babysit it and just decided to try the RS232 serial port (as that is all it has without the extended communications module) it works fine no problem and I can even get readings slightly faster from it. Using a Hart Scientific 1529 Chub-e it could give me data on all 4 channels every second without problems. I just find it a bit odd.
When I couldn't get any of the HP 3458A driver packs to work to even give a single measurement reading and just made my own using basic GPIB read/write commands using the programming manual I still have a few interesting problems in randomly when reading off the full possible 256 bytes on the bus and clearing the bus I often find garbage partial readings on the bus every now and then. I've added a few routines to do some basic checks, but it is annoying. What is really weird is when just doing basic DC Voltage reads the "-" sign will randomly be dropped from some readings (started as about 1 out of every 5, down now to about 1 out of every 10). Fortunately I'm taking several readings and averaging and taking the standard deviation with limits on the deviations and basically added a routine to say if there is even 1 negative number take the absolute value of all then make all negative, but again I find it weird.
Thanks.
-Leif
Leif King
Metrology Engineer
Oak Ridge Metrology Center

Greetings Leif,
I understand you have completed extensive troubleshooting techniques to pin-point the problem with the GPIB communication. To begin, I want to ask you a few questions to help me understand your set-up and the issue at hand.
1) Is the NI GPIB-USB-HS cable the one which cannot communicate with your instrument?
2) When using the GPIB-USB-HS, does the GPIB interface show up in MAX?
3) If yes, does the instrument appear in MAX after scanning for instruments (from what I understand in your issue, it does so in an intermittent manner..)?
4) What driver version of VISA do you have installed in your computer?
5) Are you able to communicate to the same instrument using another GPIB cable?
Thank you for trying out some of these steps again, but we want to make sure we rule out other aspects in the systems which might be affecting the GPIB communication.
As for your other issues, please post seperate threads for each so we can help you accordingly. Thanks!
Sincerely,
Aldo
Aldo A
Applications Engineer
National Instruments

RS232-to-USB converter

I have an electronic which is connected to either RS-232 serial or USB. Since the electronic cable has a RS-232 adapter, I have to use RS232-to-USB converter to make it compatible with USB port. My LabView application runs well with RS-232 port but doesn't work with USB port. The problem is that, if I use my own laptop which has LabView 7.1 installed, the problem disappears. The electronic works well with both rs-232 and USB. However, the problem appears again in other computers regardless of its version (I tried XP and 2000). I installed NI-VISA and NI-Serial. I surely checked serial port & I/O support when making an installation file. None of the methods has solved my problem yet. Any suggestions? Thanks.

Hello,
I have a few questions, the answers to which may help you and clarify the problem:
1. Can you connect directly to your computer via rs-232... do you need to use the USB port?
2. When you say, "My LabView application runs well with RS-232 port but doesn't work with USB port." what specifically do you mean? Do you get an error? If so, what error? Can you attach a screenshot of the behavior?
3. When you plug the USB-RS-232 converter into your PC, do you have access to the RS-232 resource at all? For example, if you select, Start -> Programs -> National Instruments -> VISA -> VISA Interactive Control do you see the RS-232 resource there? Can you perform a loopback test (to do this wire pins 2 and 3, and simply write and read to that serial port)?
4. Do you have any NI Serial HW products? You won't need NI-Serial installed simply to communicate with built in serial ports (or in your case a USB-RS-232 device, which should show up as an RS-232 serial port); NI-VISA will be sufficient.
Thanks and I look forward to your repost!
Best Regards,
JLS
Best,
JLS
Sixclear

Read data of sartorius scales with RS232 interface

Dear users,
I have to use a Sartorius scales with a RS232 interface.
In the attachment you see the program with which I try to read the data of this device – so far not successfully.
Therefore I have several questions:
Could somebody tell me if the structure of my program is correct? I think so, because I saw that other people created similar code. But I am not totally sure about this.
To read data of the scales, I have to send a print control to the device. In the manual of the device is written that the print command is as in the attached picture. They mention that ESC = Escape, CR = Carriage return, LF = Line feed.
So, how do I write this command correctly? Do I have to write in a string ESCPCRLF, or ESC P CR LR or ESC,P,CR,LF, or…? I am really totally lost here because I have never worked with such an interface so far.
I do not have a RS232 interface on my computer, so I use an USB to serial adapter. Do I have to adapt the baud rate etc. of my adapter in the windows device manager to the values of my scales?
When I run my program, the number of bytes at serial port is always 0. Could this be that I use next to my USB to serial adapter another adaptor to connect the 9-pin USB connector to the 25-pin connection of my scales - perhaps a connection is wrong?
I really would appreciate your help much!!
Attachments:
ScalesLV2010.vi ‏18 KB
ScalesLV2013.vi ‏21 KB
PrintCommand.png ‏5 KB

partial wrote:
Thank you for your reply.
Searching for drivers was one of the first steps I did. But unfortunately my device is so old (about 25 years) that there is no driver. I also tried to work with the programs of the LabVIEW LLB which are available from your link, but there I also get the 1073807339 error code.
Checking the cabling is for sure a good idea. So far it seems to be fine.
Thank you for your hint that the use of delays and the Bytes at Serial Port is incorrect.
But why is Bytes at Port then mentioned in this NI-document:
http://digital.ni.com/public.nsf/allkb/874B379E24C0A0D686256FCF007A6EA0
There they also mention the delay which should be used for older instruments. Since my device is about 25 years old, I thought that the use of wait is a good idea.
But perhaps you are right. So, could you please correct my program then? As I mentioned, I have never worked so far with the RS232 interface, so I really would be glad if somebody corrects my code.
Unfortunately, what NI doesn't tell you is that "Bytes at Serial Port" is a last resort, to be used only if you have no other way to figure out if a device has completed sending data. Since you have a marker - the line feed termination character - I would configure the VISA serial port to use it, and then discard the white space (the CR) at the end. That way you read exactly the data and don't have to insert a wait to make sure everything was read.
IMHO - If you have to insert a "wait" in between commands, you probably don't fully understand how to communicate with the equipment. Of course, I have worked with power supplies that are so "dumb" that the programming guide says that you have to wait x milliseconds for a command to process!
Bill
(Mid-Level minion.)
My support system ensures that I don't look totally incompetent.
Proud to say that I've progressed beyond knowing just enough to be dangerous. I now know enough to know that I have no clue about anything at all.

Question mark instead of apostrophe

In many webpages where there is supposed to be a apostrophe I see a blacked out question mark, as depicted below. Any ideas?
In the central system, for example, the MX-980 can trigger sophisticated smart macros, RS232 and relay controls via a centrally installed MSC-400 Master Controller. At each local system location, the MX-980 addresses an RF Base Station, like URC�s new MRF-260, which extends the remote�s range to 50 to 100 feet, and eliminates the line-of-sight requirement. In any room with a projector, lighting switch or other IR-controlled device not connected to a central MSC-400 or local MRF, the MX-980�s built-in IR signal is effective at a range of 30 to 50 feet.

Thanks for the reply. If, while in Safari, I click View:TextEncoding and choose Western ISO Latin 1, the fonts are normal. Choosing Unicode, Default or Western MAC OS, the fonts are not correct.
So, I figured I'd choose Western ISO Latin 1. Problem is, when I close Safari and re-open, it's back to Default and displays the fonts incorrectly again.
I guess I'm not sure which text encoding is proper for the United States and how to set that proper encoding as default.
Thanks for any more help you can provide.

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