ERROR 1073676294 ????? VISA READ...!!

Dear All
I am Writing and Reading the data from one EEPROM,interfacing with a PIC16F690,like this i am swiotching 240 EEPROM with MUX,through LabVIEW serial communication pallets,I am controlling the Reading/Writing, but some times ERROR 1073676294 ????? VISA READ...!!,once this error occurs next  all EEPROM chip are not able to READ /WRITE,if unplug the powersupply and plug it back,then LabVIEW can Read/Write,i am not able to fix this error,please advise me whether problem is from LabVIEW or MICROCONTROLLER,I used delay function but also same problem.
Raikar A G  

1073676294 is not an error but a warning saying that you got exactly the number of bytes you requested in the Visa read, and that there might be more bytes still remaining in a serial buffer.  (Which I've always considered this a stupid warning, because as a programmer, I'm going to assume that there might be more data in the buffer than I have just pulled out.)
The warning should not cause any problems in your LabVIEW code, nor should it cause a problem with your serial communication.  So if you lose communications with your microcontroller, it must be something else going wrong.

Similar Messages

  • VISA Read Timeout and VISA Write not working

    I'm writing a program that sets a triangle wave pattern voltage (using Triangle Wave VI) to a DC power source (GWInstek PST-3202) through a RS-232 connection.  I know my instrument parameters are set up correctly because I've been able to control this power source using a different VI with the same parameters.  I also know I am connected to the power source because I can talk to it using MAX.  I have a string indicator before my VISA Write statement that shows me the command being sent to VISA Write.  It shows the correct syntax for setting a voltage on this instrument.  However, when I run the VI, the voltage is not changed on my instrument, even though the correct command is sent to the instrument.  After the VISA Write operation I have inserted a VISA Read function in order to read the newly set voltage from both a numeric and a waveform indicator.  Using the Error Out cluster I am able to see that there is a timeout error from VISA Read.  I thought perhaps I needed to clear or flush the buffer after each Read statement, but that didn't work either.  I'm stumped as to why VISA Write isn't writing to the device.  I have included my VI below, as well as the initialization subVI for the power supply.  
    Attachments:
    Triangle Volt Mod.vi ‏27 KB
    GW Instek initialization.vi ‏18 KB

    Yep, you need to append the End of Line character to the end of your command.  And for your read to work properly, you need to request the data.  That requires a querry command to be sent.  Look closely at the differences in command and communication structures between your working VI and your mod.
    There are only two ways to tell somebody thanks: Kudos and Marked Solutions
    Unofficial Forum Rules and Guidelines

  • VISA Read over USB Problem: After a while the xBFFF0015 Timeout Error occurred

    Hi,
    I have trouble using labview with my non-NI USB device:
    The device is an analog input DAQ board. I was able to setup communication with the board using a VISA driver specifically created for this board and direct FW calls using the product's firmware specification provided by the manufacturer.
    This method has been working pretty good so far, but when I try to get large amount of data (64k samples @100ksps), the VISA Read returns the 'VISA: (Hex 0xBFFF0015) Timeout expired before operation completed.' error.
    Please see the attached screenshot of the block diagram for details.
    First, an 'analog input scan start' command is sent to the DAQ device, and then the vi tries to read all collected data from the device, once the right amount of data retrieved, or no more data is available the data collecting process (the while loop) ends and an 'analog input scan stop' command is sent to the DAQ device.
    The data collection starts with no problem, but after a while, in loop# 400, the VISA Read hangs and then returns the error mentioned above.
    I tried to increase the time out value, but it didn't help, the error occurred after the same number of loops, the VISA Read got hosed and the error occurred after the longer timeout expired.
    I also tried to add some delays in the loop, but it didn't help either.
    I am not sure what do I miss here and I would highly appreciate if anyone could give me some guidance how to solve this issue.
    Thanks,
    John
    Attachments:
    usb-read.png ‏18 KB

    I just wanted to specify that this is not an NI board avoiding to make people think this is a hardware issue. And I think that the rest of the code is irrelevant in this case.
    I believe that I don't use the VISA functions correctly. I assumed that someone who used these functions before would be able to point out the obvious steps missing in the data collecting process using the VISA functions.

  • NI VISA read stops at zero character, returning an 0xBFFF003E error

    Hi
    I’m trying to read some serial data from a UUT using the NI-VISA read function. The data is mostly text but does include some control codes. The first of these appears after the ‘OK’ in the Serial Bytes window on the front panel. More text should follow but for some reason, the read function stops at the first zero character (index 144 in the Byte Array), and returns an 0xBFFF003E (-1073807298) error. I found another thread where someone had a similar problem and I’ve tried the fix for this plus a few other things, but nothing’s worked. If I use Hyperterminal, the entire data block is returned as it should be.
    I wondered if this was anything to do with the 7.1 version of Labview I’m using (upgrade is on the cards). The version of NI VISA I’m running is 4.2.
    Very much appreciate any thoughts.
    Thanks
    Bruce

    The error code itself is a generic VISA error which often happens with USB to RS-232 interfaces. Does your device connect to the PC through USB as a virtual COMM port? If so what chip and Windows driver is it using?
    Also your function somehow looks wrong. The only criteria for the read loop to terminate is if there is an error on the VISA read or the Teststand termination status gets true. Generally if you use VISA Bytes at Serial Port you are almost always doing something wrong! That function does absolutely not synchronize with anything in your data. You will read whatever is there at that moment and that could be a partial message, no bytes at all (LabVIEW is typically many times faster than any serial device even if it is super high speed), or multiple messages.
    Rolf Kalbermatter
    CIT Engineering Netherlands
    a division of Test & Measurement Solutions

  • Error -1073807253 occurred at VISA Read in transient SR830.vi VISA: (Hex 0xBFFF006B) A framing error occurred during transfer.

    Hi,
    I am have written a program with labview to make transient c-v measurement using a stanford research SR830 lockin amplifier. The program seems to be runing fine, but sometimes it is givvibg an error:
    Error -1073807253 occurred at VISA Read in transient SR830.vi
    Possible reason(s):
    VISA:  (Hex 0xBFFF006B) A framing error occurred during transfer.
    Error -1073807253 occurred at VISA Read in transient SR830.vi
    Possible reason(s):
    VISA:  (Hex 0xBFFF006B) A framing error occurred during transfer.
    but if I press ok, the program again starts running. What might be the poblem? BTW I googled a bit and I see that in the labview topic "RS-232 Framing Error with HP 34401A Mulitmeter" by pkennedy32 this is what is said about framing error:
    ""Framing Error" in an RS-232 context means a very specific thing - when the receiver was expecting a stop bit, the line was not in SPACE condition. This can be the result of:
    1... Baud rate mismatch (although other problems would likely crop up first).
    2... Data Length problem, If I send 8 data bits and you expect 7, the stop bit is in the wrong place.
    3... Parity setting mismatch - If I send 7 data bits + parity and you expect 7 data bits and no parity, the stop bit is in the wrong place.
    4... Mismatch in # Stop bits - If I send you 7 Data bits + parity + one stop bit, and you expect 7 data bits + parity + TWO stop bits, the second one might not be correct, although most devices do not complain about this.
    But, I must say that this is the same com port setting that I use to measure c-v hysterysis, but I never gt this error there.
    I attach the program herewith for your kind perusal. Please help me resolve this issue.
    Thanks in advance.
    Solved!
    Go to Solution.
    Attachments:
    transient SR830.vi ‏94 KB
    csac.vi ‏8 KB
    sr830 initialize1.vi ‏15 KB

    @Dennis Knutson  you are right I checked the read indicator in backslash mode, and instead of a \n it is sending \r. So I changed the \n in my write strings to \r. But, if I keep the CLOSE VISA outside my loop instead of inside as you suggested, the termination character appears to come in the middle of the read string instead at the end. And since the read terminates at the \r so it is displaying some junk value before the \r, but if I put the CLOSE VISA outside the loop and play along with the bytes at the read buffer, I see the whole read string with the \r  at the end of the string. But, whenever the values are in exponential form (when close to zero) like 6.938839 e-5, I always get a time out error whatever be the timeout that I put at the VISA initialize. And subsequently, if I stop the program and run it again the machine program hangs and I donot get any reading. Then after I close it again and start, sometimes it hangs for some more or starts working. If I put an arbitrarily large byte count at the READ VISA, then I always get the time out before the operation completed error.
    @ Ravens Fan I have removed the CSAC VI altogether and taking the CH! And CH” reading separately, instead as one string. So, no more issues with that.
    I use the control at the delay so that I can choose how much delay I want to set, and I use the math operation because I am using adding up the delay time to keep track of the time elapsed. Because in the end I have t plot a time vs. CH! And CH” readings.
    I am not sure but probably I am making some silly errors. Please help me out. 
    Attachments:
    transient SR830-2.vi ‏103 KB
    sr830 initialize1.vi ‏15 KB

  • How do I avoid Error 85 in Scan From String scanning VISA read buffer?

    I have encountered an Error 85 with my Scan From String VI. I have a timed
    loop to read data from a device (flowmeter) using a serial port. This device takes
    periodic measurements and sends the reading which contains a numerical value to the serial port COM1. It cannot be read continuously, and the period
    between measurements may vary, so I decided a timed loop would be better than a while loop.
    The VI begins with VISA Configure Serial Port and then
    goes to a VISA Write which sends the message to the device to begin
    taking measurements. After this, the device usually says "TAKE FLOWMETER READINGS" to the terminal, thereafter only sending numbers. Then begins my timed loop containing VISA Read. I
    am taking the read buffer two places.
    First, I am taking it to an Array to Spreadsheet String with the
    Format String %.3f, as was in the Write to Text File example. Then I am
    using Concatenate Strings with this string and also a string containing
    the System Time. This string goes to Write to Text File, which I have
    configured using Open/Create/Replace File outside of the loop.
    Second, I am taking the read buffer to a waveform chart. I thought
    it would be a good idea to use Scan From String to convert the string
    into a DBL which I am then sending to the waveform
    chart.
    I am not sure if the initial "TAKE READINGS" message is giving me an error. I was able to get one reading saved to my text file from the device.
    Also the format string for my Scan From String is %.3f
    I am getting the Error 85 at the Scan From String only sometimes.
    When this happens, there is no data being written to the text file. But
    other times, I get data and it writes to the text file just fine (but
    rounds to nearest whole number).
    Any help would be greatly appreciated! This serial port device has been giving me a lot of trouble.

    Is this what you mean? Did I wire the shift registers correctly?
    I didn't know if you meant to Concatenate before Scan From String or Concantenate before or after VISA Read?
    Message Edited by YeungJohn on 11-20-2008 03:48 PM
    Message Edited by YeungJohn on 11-20-2008 03:49 PM
    Attachments:
    SerialShiftVI.JPG ‏87 KB

  • Error x3FFF0006 in VISA Read/Write

    Hi,
    I am getting this error message sometimes in VISA read and sometimes in VISA write. Its not consisten. Its only thrown in certain VIs. What could be the issue? I am attaching my main VI, where I configure serial port, and the VI where this error is thrown.
    Thanks.
    Attachments:
    Main.vi ‏39 KB
    Error.vi ‏30 KB

    It's a warning and not an error.
    The VI that is showing the warning is a little weird. You configure the serial port to terminate the read with a termination character but then when you do a read, specify the byte count and if the bytes read does not equal what you specify, you try to do another read. You usually don't do both.
    If you specify a termination character with the VISA Configure Serial Port, the VISA Read will terminate when the termination character is detected. If you specify 100 bytes to read and there are only 50 bytes and a termination character, all you will read is 50 bytes. If you disable the termination character detection, you will always get the warning. In this case, as long as you use the VISA Bytes at Serial Port to verify that there really isn't any more data in the buffer, you can simply ignore the warning.

  • Parity error occurs in VISA read when building an executable

    Hi,
    I am doing some serial communication in LabVIEW and have battled for a long time with parity error where it appeared as a lot of 0's were added to the data I read through VISA read. I fixed my problem according to this description:
    Can I Do 9-bit Serial Communication Instead of 7 or 8 bits?
    Where i modified the visa ini file to disable error replacement. This seemed to help out the problem - at least i got the data i expected, until i built an application.
    When i build and EXE the problem occurs again when i run the application on another computer - not the computer on which it is built. I have made sure to include a customed configuration file, i.e. to include the modified visa.ini file to make sure that the error replacement is disabled in the application as well. When i look in the configuration file that follows the application it also appears as if the error replacement is disabled, however, it seems not to work since a lot of 0's are once again filled into my dataset.
    I have of course made sure that the serial port setting are set up correctly.
    I am using LV2013.
    Anyone tried this before or is able to help somehow?
    Thank you
    Nicolai

    Sure, I have attached my VI - however i'm not sure it provides any useful information in this case. What I am doing is simply reading a serial port every 750 ms, accessing specific data in it and plotting in graphs. The VI works perfectly fine on the development computer.
    I don't think the VI or the serial port are what's preventing me. It seems like the configurations in my visaconf.ini file are not transferred to the deployment computer. I have tried the following from the knowledge base:
    How to Include VISA Settings in a LabVIEW Installer
    Why Does Serial Communication Not Work on my LabVIEW Deployed Executable?
    Storing VISA Aliases and Moving Them to Another Machine
    I can also see that the 'DisableErrorReplacement' parameter is set in the .ini file that comes along with the application, but it seems like it is not applied since I keep receiving all these annoying 0's that ruin my data.
    As you can see in the VI i configure my serial port in the 'false'-state, and then on the development machine I have just added 'DisableReplacementError=1' to the visaconf.ini file which solved my problem before trying to distribute the app.
    Hope some of you guys can help.
    Best regards
    Nicolai
    Attachments:
    Read datablock.vi ‏55 KB

  • VISA READ timeout error - multiple GPIB resources

    Hi,
    I am working on a 3 instruments GPIB network (optical attenuator, fiber amplifier, spectrum analyzer), controlled using VISA sessions in Labview. When run separately, the three corresponding VIs (which are located in three different Labview projects) work as expected. However, when they are ran simultaneously, one of them gives VISA READ -1073807339 timeout errors. These errors seem to happen when an other instrument is sending / receiving data / instructions at the same time as it is.
    The exact context for these error is either :
      -  an other VI is running, which includes sending several queries and reading the answers every 100 ms,
      - upon starting the failing VI, I get a  timeout error from one of the first subVI containing a VISA READ operation to be executed (sometimes initialize.vi (in state 1), sometimes one of the subVIs ran from the Idle state (state 0) upon timeout of the event structure).
    or :
      - the failing VI is running,
      - upon starting an other VI, which includes repetitively sending queries and reading answers, the failing VI throws an error from one of the first subVI containing a VISA READ operation to be executed (one of the subVIs ran from the Idle state (state 0) upon timeout of the event structure).
    What I tried :
      -  gradually increasing the delay between the VISA WRITE and READ operations for the relevant instrument (from 10 ms to 10s), to no avail. More puzzling is my obseration that, when this VI is run alone, increasing the WRITE / READ delay leads to the same timeout errors. I could not find any mention of such behavior through google and forum searches. Hopefully this can point to a solution to the main issue,
      - switching between synchronous and asynchronous VISA WRITE / READ operations,
      - reordering the GPIB network from a star topology to a linear topology (all three instruments do have different GPIB addresses in case anyone wonders).
    My thoughts :
    It seems to me that the error is related to a delay introduced between a VISA query and its associated read operation by the transmission of another query to another instrument in the same GPIB network. However I have no idea why transmitting a query to another instrument would introduce such a delay, or why this delay would lead to a timeout error (and only from one instrument, while the write / read VIs in each driver are basically the same). Hopefully a more experienced Labview-er will be able to shed some light on my issue.
    Included is the project containing the failing VI (main.vi) and the custom driver it makes use of. 
    Solved!
    Go to Solution.
    Attachments:
    Manlight EDFA Control - Failing VI.zip ‏73 KB
    EXFO FVA 3150 - Driver.zip ‏348 KB

    Thank you for your input crossrulz. This is indeed what I realized while looking into semaphores.
    Let me first make our architecture clear so that I'm 100% certain we are talking about the same thing. We have a NI GPIB-USB-HS GPIB Controller connected to a linear GPIB network of three instruments. I was convinced that a network allowing up to 15 instruments to be connected at the same time would allow for parallel operation, but it seems I was mistaken.
    I like how semaphores work, and I don't see any obstacle to gathering all these VIs into one project. My conception of a Labview project was that one Labview project was intended to gather subVIs, libraries and controls used in a more complex "main" VI, which would ultimately be made into a single standalone executable. It seems I was mistaken too and that a single Labview project should be used to gather several standalone VIs designed to work together, and their subVIs. Hopefully I got it right now.
    The other option that you suggest for accessing the same GPIB bus from different projects (having a TCP control interface running and controlling communications through the bus) might indeed be a bit overkill for what I'm tring to achieve, and I would need to spend too much time learning and developing it.
    A last option I looked into is the VISA Lock Async VI, but I don't understand yet if 1. locking the VISA session for an instrument in the bus would lock the entire bus ; 2. if it would be possible to use this approach with VIs running in different projects and 3. if it would not just yield errors when one VI is trying to access the locked GPIB bus instead of making it wait until the resource is available.
    I'll look further into these options today, but would appreciate any additional information / advice you might have. Thank you.

  • VISA read timeout error

    Good day to all,
    I have this problem with my LabView program. It is being used to interface with a Energy Meter to retrieve the data. I am able to execute "Open" and "Write" VISA, but am unable to execute "Read" VISA. Attached below is the screenshot of the error.
    EKI1521 is being used to interface serial connection from the meter to ethernet, connecting to the computer with
    labview program. Attached are the settings for the EKI1521.
    This is extracted from the main program after narrowing the problem down to the VISA Read function. The subVIs in this program are proprietary protocols of the meter and does not contribute to this Reading error.
    It might be interesting to note that I am able to run another program to interface with another meter using Modbus protocol. It also used the same EKI1521 with the correct VCOM settings. (This should free the EKI1521 from any faults). 
    Thanks & Regards,
    Andrew
    Attachments:
    1.png ‏169 KB
    2.png ‏210 KB

    Hi,
    Stop me if I make a mistake, but you don't set Visa properties in your Labview code (type, baudrate... etc).
    Best regards,
    V-F

  • Erreur 1073676294 dans VISA READ

    Bonjour,
    comme l'indique le titre, j'ai une erreur (1073676294) dans mon VISA Read.
    Lorsque j'execute mon VI principal, mon sous VI contenant ce VISA apparaît.
    Comment faire pour qu'il n'apparaisse plus?
    Cdt
    Résolu !
    Accéder à la solution.
    Pièces jointes :
    Test Machine à états.vi ‏31 KB

    J'ai effectué les configurations indiquées, mais malgré ça, mon sous VI s'affiche toujours..
    Pièces jointes :
    Ecriture_T_Consigne.vi ‏29 KB
    Visa_écriture.vi ‏20 KB
    Cadencement Maître_Esclave_.vi ‏42 KB

  • Visa error -1073807339 when reading or writing to com 2

    Good morning,
    I am using both com 1 and com 2 to communicate with instruments using Labview 7.1 and Windows XP. Com 1 which works without any problems is communicating with a HP 34970A and com 2 which sporatically works is communicating with a Valhalla 2430 power analyzer. When I get the error, I open MAX and com 2 has an explanation point indicating a problem.
    Thanks for your help.
    Everett

    Hello again and thank you for all the responses. Valhalla charges money for their driver so I doubt they would want it posted in the discussion forum. I ran NI-Spy and will attach the logs. I also changed the byte count from 32 to various lower numbers but 21 seems so far to operate without an error running the Valhalla VI only. This afternoon I will try it again in the program to see if an error occurs or if I don't get my data sometimes. Capture 1 was done using max and open visa for com 2. I ran it several times. Capture 3-1 is after I changed the byte count to 21 and added some delay on the VISA read.
    For some reason it won't let me post a .spy extension
    The file does not have a valid extension for an attachment. jpg,gif,txt,xls,vi,zip,doc,bmp,llb,pdf,png,seq,c,h,cpp,cs,vb,ini,gz,ctl,scr,ico,tar,z,uir are the valid extensions
    Everett

  • The vi is identifyng the number of bytes to be read but the VISA Read vi is not able to read the data from the port.

    We are trying to communicate with the AT106 balance of Mettler Toledo.The VI is attached.
    We are sending in "SI" which is a standard command that is recoginsed by the balance. The balance reads it.The indicator after the property node indicates that there are 8 bytes available on the serial port. However, the VISA read VI fails to read the bytes at the serial port and gives the following error:
    Error -1073807253 occurred at VISA Read in visa test.vi
    Possible reason(s):
    VISA: (Hex 0xBFFF006B) A framing error occurred during transfer.
    The Vi is atttached.
    Thanks
    Vivek
    Attachments:
    visa_test.vi ‏50 KB

    Hello,
    You should also definitely check the baud rates specified; a framing error often occurs when different baud rates are specified, as the UARTs will be attempting to transmit and receive at different rates, causing the receiving end to either miss bits in a given frame, or sample bits more than once (depending on whether the receiving rate is lower or higher respectively). You should be able to check the baud rate used by your balance in the user manual, and match it in your VI with the baud rate parameter of the VISA Configure Serial Port VI.
    Best Regards,
    JLS
    Best,
    JLS
    Sixclear

  • Visa Read Timeout Occurs with multiple Reentrant VI Calls

    I have written a test application in Labview (6.1) which will be used to test (burn-in) up to 15 serial instruments through a 16 Port USB->RS232 Hub. Here's how it works:
    When the App loads, I am transmitting a Connect command to each of 15 com ports (one-at-a-time) using VISA. If I receive the proper response from the unit on that port, I add the port to an array and continue on to the next system. Once I've found all systems on the hub, I wire my array of active Visa references to a for loop in which I open up to 15 reentrant VIs which will run in the background in parallel. Each of these reentrant VIs (all are idential with the exception of the Visa Resource they use) running in the background are sending commands to the the respective instrument and receiving a response. One Function in particular "Get Unit Status" is important and the response determines whether or not the instrument is functioning correctly. Here's the problem -- In my Main Loop, I am continuously acquiring indicator values from each of the reentrant VIs that are running in the background. After a period of time (not consistent) I will lose communication with a port (the symptom is no response from the unit). I've looked closely at the COMM engine I created and found that the Visa Write function is completing without error, then when I perform a Visa Read I immediately get the "Timeout occured before operation completed" error (please keep in mind that this occurs after 100-5000 successful attempts at writing/reading). Eventually another port will drop out, followed by another. This seems to stop occurring and the remaining systems run to completion without a problem.
    Some background on what how I'm setting up my Visa Sessions...
    When I originally scan for systems (before I load and run the Reentrant VIs)
    - Init Visa Port
    - 19200, 8, N, 1
    - Use Termination = True
    - Timeout = 400mS (I've tried larger values already) 400mS should be plenty
    - Termination Char=13 (/r)
    - Open Visa Session
    - Visa Write "CONN18/r" (the command required to connect to my instrument)
    - Visa Read with 1 for requrested byte count to read 1 byte at-a-time, concatenating the results until /r is received (or 1000mS timeout occurs -- this is not a VISA timeout) I've also tried 16 for requested byte count and just waiting for Visa to timeout -- both methods work.
    Once all 16 ports are scanned I Close ALL of the ports using the Visa Close Function.
    It is important to know at this time that I "AM" using proper wiring flow to ensure open occurs before write, write occurs before read, etc.
    I'm assuming at this time that all of my Visa sessions are closed.
    On to the Reentrant VIs:
    Inside each reentrant VI I first Initialize all of my variables and Init/Open a 'New'? Visa session using the same parameters mentioned above.
    Then I enter the "Run" case structure where all of the communication begins.
    I am using the same Communications Engine to operate the instrument as before (the only difference being that all of the VIs in the comm engine are now reentrant and operate at higher priorities) I have actually saved two different versions of the engine (one for the reentrant calls and one for when I first scan for systems from my Main GUI).
    When I init the reentrant VI, I am placing the Duplicate Visa Resource output of my Visa Open Function on a shift register. When I enter the Run case, it takes the Resource from the register on the left, wires through any Comm Engine Vis then back out to the shift register on the right and keeps going for a 12-hour period or until "Get Unit Status" has returned 60 naughty results.
    On my Main GUI I am continuously (every 500mS) I am Getting certain Indicator Values from each reentrant VI AND I am also setting some control Values on each reentrant VI. There is no VISA interaction between each Reentrant VI, and the Main GUI.
    As I said earlier, up to 15 systems will run for a time, then one will stop responding, followed by another, and another until a few remaining systems will run to completion.
    Any advice as to why I'm encountering the timeouts with the VISA read fucntion as I have metioned would be appreciated. I managed to find one suggestion which uses the Bytes at Port function to ensure there is data at the port before doing a Read otherwise, skip the read and retry the whole operation -- I haven't tried this yet.
    Sorry for the wordiness of my question. If anyone would like some screen shots of portions of my code (I can't submit the actual code because some of it is confidential) I'd be happy to post them.
    Doug.

    Hi Doug,
    The first thing I would recommend is the solution you have already found, to check and see if there is data at the port before attempting a read. I would be interested to see if this will solve the problem. Does there seem to be any trend to which ports have this timeout error? How many ports does it cut down to before operation seems to continue as expected? Does this number vary, or is it always the same number of ports? I think the best thing to do will be to identify constant attributes of how the error is occurring so that we can narrow it down and see what is going on.
    John M

  • How to use multiple visa read in one program

    hi
    i am working at Hameg HM8143 power supply i want to measure voltage and current simultaneiously and use the measured values for further calculations. for this i used two visa read blocks.
    >>>>>>the measured values are shown in the same visa read string however i want it to be shown sepetately,
    >>>>>>One of the VISA read block gives error. so i want to know how to use VISA read to get current and voltage simultaneously in seperate strings
    >>>>>>than how to convert strings to numbers  for using them for my calcultions.
    i am attaching screen shot as well
    Attachments:
    screenshot.JPG ‏164 KB

    you can not use a single serial to send 2 commands simultaniously?
    There is a single serial line so one command has to be before another.  This doesnt mena that you can not read from 2 seperate threads but will have to ensure that there is a locking mechanism to make sure that your queries are atomic.  In labview encapsulating all communications can be done with an action engine which will allow for concurrent execution with automatic blocking of your resource (serial device).
    Paul Falkenstein
    Coleman Technologies Inc.
    CLA, CPI, AIA-Vision
    Labview 4.0- 2013, RT, Vision, FPGA

Maybe you are looking for