用Vc＋＋开发的一段代码，用于从示波器中读取内存的波形数据，连接通过LAN.单步调试时，viRead能够读出仪器缓存的数据，1413字节，但是当运行这段程序时，viRead就只能传回12字节的数据，也就是仪器缓存中数据快的头:#9000000000，viRead的返回值还是VI_SUCCESS.
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viRead() in VC＋＋
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suggestion for serial communication thermometer with ASCII commands (for teaching purposes)
Hi everyone,
maybe off topic but I can't find good answers on google.
I am teaching basics about LabVIEW programming to students and I would like to make an exercise where they have to create a small simple interface to program an instrument (select chan num XXX, start reading with interval...) and continuously read answers from the instrument, extract data, plot it on a graph and save in log file all inside some parallel while loop... Nothing fancy, just the basics.
I therefore looking for a "cheap" (around 200 euros) digital thermometer with 1 or 2 channels (RTD or thermocouples) which has a digital screen display, a serial port rs232 for communication with the computer based on ASCII commands and a good documentation which describes communication protocols parameters and lists of ASCII commands, because I want the student to spend a bit of time looking for the information in the documentation but it has to be done within reasonable amount of time.
A great thermometer for that is the ASL F200
https://www.isotechna.com/F200-Precision-Thermometer-p/f200.htm
but it s a bit pricy for my use here and I don t need such accurate instrument.
Maybe someone has good suggestions for me
thanks a lot
regards
Hicham
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Encoder Mike 18011 Controller and NI Max
I am currently working with an Oriel Encoder Mike 18011, with no access to the original software floppies. I am trying to communicate with it over serial, but I am having issues. I connected the controller via rs232 and opened NI Max to communicate with it over serial.
When the Data was read on the press of the rem/loc button when it was local, this was the result:
1: Read Operation
Return Count: 10 bytes
\FC\DF\1F;\7F\DF\FF\FE\DC\FC
Can someone interpret this data/help me with communicating with the Encoder Mike?
I am using a non standard serial connection (shown in manual) connecting the pin 7 of a DB 25 and a DB 9 to each other as ground. A DB9 is connected to a DB25 with only pins 2,3, and 7 used on each connector, neglecting the tying together of pins mentioned in the manual I am also using a CommFront USB to Dual RS-323 Converter Model Number USB-232-A-1
The manual is here:
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GPIB communication issues between PC and device
Hi ,
I have a device, which has an older GPIB version(it is DOS95 base I think). And I want to hook it up to a WINDOWSXP PC which has an updated version of GPIB, but whenever I do it, the WINDOWS XP can't detect the device.
The device, can run on an old DOS based computer. I tried connecting to the device in parallel (using the windows XP PC), so I could check what GPIB commands trhe device is throwing(using NI SPY). But whenever I do that the device wont communicate. However, when I remove the parallel connection to the Windows XP, the device can communicate again.
Can you help me on this?
Thanks!
Appreciate your help
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Basic CAN Bus Example
Hi everyone,
I have questions about CAN Bus. It is the only communication bus that I did not use in LabVIEW. So I do not know fundamentals of CAN in LabVIEW.
To understand similarity, I will attach a VI that I wrote in LabVIEW to communicate with a device without any NI Hardwares with RS232 cable. This VI works. There is no problem.
But as I said, I have no experience with CAN Bus. I created a CAN VI which is similar to the RS232 VI. But in RS232 VI, the data packet came in hex (string) format since I used VISA functions.
In CAN VI, I have specification of device. I know numeric representations of variables. But I guess I can not use VISA functions. So the hex packet will come in string or not??
Please just make a basic CAN example that is similar to the RS232 VI I attached. In this way, I will be able to imagine what happen.
Thanks
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Modbus CRC16 generation question
Dear guys
I have a problem in the edit the CRC16 code,i can't get the CRC16 checksum is same as the correct command list showing.pls help to have a look about my Vi,if have a bug or no attention point,thanks a lot.attached my vi,fyi.
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Communication to Vötsch oven
Hello, how to communicate to a Vötsch oven?
(in the past the name of the company was: "Haraeus Vötsch" now: www.weiss-technik.com)
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How to find USB device ID after set up in NI VISA
After NI VISA creates and installs the driver to a USB device, it is required to find the VISA instrument description to the USB device.
You can easily find that long string in MAX if the driver is properly installed. But my question is what if you don't have MAX installed in the PC. How do you find the descriptor string without MAX?
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How does switch matrix card PXI 2535 work without GND?
Hi guys,
I am using switch matrix PXI 2535 for continuity testing. When i see the datasheet i found that there is no GND reference, i mean there is no GND from connector. can anyone tell me how does the card work and what would be the GND reference for the instrument is it Tester GND or anything else?
Regards,
Alekhya
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GPIB Analyzer Software Install Error
I am trying to install the GPIB Analyzer so that I can debug a 488.2 interface. However, after selecting the file path to install to and hitting continue, I get the error:
"Could not open the file named 'C:\Users....\CVIRT31A.EX"
The file is located in the same folder as the rest of the install. What's the deal?
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GPIB Analyzer Software Install Error
I am trying to install the GPIB Analyzer (http://digital.ni.com/public.nsf/allkb/848F027883BD6429862571B8001DFEDC) so that I can debug a 488.2 interface. However, after selecting the file path to install to and hitting continue, I get the error:
"Could not open the file named 'C:\Users....\CVIRT31A.EX"
The file is located in the same folder as the rest of the install. What's the deal?
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Instrument I/O Assistant causes VISA error 0xBFFF0072, VISA resource available but cannot access it
I'm running LabVIEW 2017 on a desktop PC. The PC is connected via a USB-to-serial adapter to an RS-232 serial port on a Tektronix DMM4040 multimeter.
I place an instance of "Instrument I/O Assistant" onto a VI's block diagram. Using the Instrument I/O Assistant "wizard" dialog, I can communicate with the DMM4040 as I create the sequence of steps to be executed--e.g., Select Instrument, Write, Query and Parse, etc. If I click on the wizard's "Run>" button, the script runs fine; everything works.
Now I click on the wizard's OK button to close the dialog and render the code in the Instrument I/O assistant node on the block diagram. When this process completes, I click on the VI's "Run" arrow (CTRL+R) to execute the VI.
At this point the error dialog shown in Figure 1 appears:
Figure 1
If I close all LabVEIW programs, restart LabVIEW, open the VI, and then run the VI, the program runs normally; no error dialog appears.
If I now open the Instrument I/O Assistant wizard, and then immediately click OK to close the wizard, I get the error message again when I run the VI.
So it appears the Instrument I/O Assistant code has a bug(?) that is perhaps failing to release system resources associated with the virtual COM port the DMM4040 is using, and this is causing the error.
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How to save or recall a state in Keysight PXA 9030
I am using LAN interface to control my PXA 9030A analyzer and i am unable to find the option to recall a state of the analyzer.Could anybody help me in this context?
Thanks,
Wazib
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Serial communication with data acquisition device issue
Hello everyone,
I am using a DATAQ DI-145 data acquisition device to obtain values that will correspond to voltage amplitude. I have a working code for such using ActiveX controls, however it is a bit slow and dependent on externally provided software, so I am experimenting with serial communication. I read the (attached) device's protocol, and I installed visa drivers for the instrument to communicate in LV. Reading around, I created this code (attached sniplet), however neither the read nor write options seem to properly work. There is a series of basic commands in the protocol, out of which I also get no response (and occasionally the VISA timeout error). The same happens when I try the VISA test interface in MAX (for some reason i also get more ports than the instruments i have in).
Specifically, I quote from the protocol: '' Responses to this set of commands include echoing the command, followed by a space (0x20),
followed by the response, and ending with a carriage return (0x0d). For example, the command "info 1" generates the following response ''info 1 1450(0x0D)'' . Does this mean I need a carriage return termination character to be enabled on read/write? I fiddled with both timeout (2s,10s) and termination character enable/disable in test panel and not much seems to change when trying to send info\s0 sommands etc.
I'm very new to serial communication so I might be missing something obvious (for example, why are transmit and receive buffers on 0? what does it mean?) or doing something wrong. Would appreciate some guidance.
Finally, since I am trying to avoid using the visa property bytes at port, does me setting a bytes to be read control make me miss any of the continuous stream? And is the empty string and feedback node sufficient to distinguish between different measurements?
Nafsika
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visa delay
hi
I am using visa to receive some data from a microcontroller (AVR) , but between send a string by AVR and receive it by Labview have a very big delay. (sending of data by AVR === no delay & receiving by Labview ==== very big delay) . what is the problem???
thanks
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VISA error -1073807360
I have searched the board and not found an exact example of what I am experiencing. The application I am using has run successfully for years and has had no problems. All of the sudden, this error pops up. The com port drivers are all up to date, and as far as I know there have been no updates or changes to the machine that it is running on. I have attached the VI for good measure, any suggestions as to where I should look next?
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Secuencia de leds guardada por usuario
Cordial saludo para todos.
Me piden un instrumento virtual en el cual el usuario pueda diseñar una secuencia de luces la cual se debe visualizar en un conjunto de 10 leds en linea, las condiciones son las siguientes:
1. El usuario determina la cantidad de secuencias que guardara.
2. El tiempo que dura encendido cada estado, donde el tiempo ingresado sera igual para todas las secuencias.
3. El sentido en el que se visualizaran las secuencia diseñada, de primera a ultima o viceversa.
Adjunto lo que tengo hasta el momento, esperando su colaboración.
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Connecting to YOKOGAWA 2533 Power Meter via GPIB
Hi,
Pre-edit: This is the first time i am using GPIB interface. I read the GPIB tutorial of NI so far.
Currently, I am trying to connect a YOKOGAWA 2533E via GPIB. I have LABVIEW 2017 and NI-MAX 17 The current situation is:
- The device is in addrassable mode and has the address of C (12).
- I have a advantech model GPIB PCI card in the computer.
- I have bought a GPIB cable and connected the device to computer.So far so good.
- I have made the GPIB config from NI MAX set the address and the timeout etc. When i try to query smthng like *IDN? i get a timeout error which indicates that I think i made some config wrong or the device is inreachable. So i wanted to download a device driver.
- I downloaded the device driver from:
- When i try to convert the .fp to Labview driver from Instrument Driver Import in Labview i get the error below
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NI 488.2 Drivers not installing correctly on MacOS 10.13.1
Hi all,
I've been trying to install the NI488.2 drivers for GPIB instrument control on a system running the latest ver sion of macos (10.13.1) and have so far been running into the same issue. No GPIB instruments are detected (standard USB is fine) and the 488.2 trouble shooting wizard states that the 488.2 drivers have not been installed correctly. I've tried multiple restarts and reinstalls and have also tried completely uninstalling both the 488.2 drivers and the standard NI-VISA driver before reinstalling. No luck so far with the troubleshooter always returning the same issue.
I'm wondering if this might be a problem with running the latest version of macos? If anyone had any bright ideas that would be great!
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VI_ATTR_FIND_RSRC_MODE documentation?
I have a PXI chassis. By running NI-MAX and tracing with NI-IOTRACE I can see that MAX calls viSetAttribute(session, VI_ATTR_FIND_RSRC_MODE, 0x8018) as the first order of business; subsequently, it can enumerate all the PXI slots with viFindRsrc("/?*") - i.e. viFindNext returns all the PXI*::INSTR resources. Without setting that attribute, I can only find PXI*::BACKPLANE. I can't find any documentation for this attribute.
Please indicate where I can find documentation for this attribute, as I'd like to enumerate PXI slots.
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