Thang Nguyen

Hi, I have an issue and need the recommendations form you. Currently, I am working on an old project which my company did it with LV 7.0. This is a big project and take a lot of time to develop. This is the reason why we try to find a way to move the program from 7.0 to 8.5 without rewrite the whole thing. The problem is this project use DSC and there are a lot of tags. My question is there is anyway to move the program from LV 7.0 to LV 8.5 by converting the tag engine from 7.5 to 8.5. This relates to another issue as the DSC VI used to read and write data. I hope that by your experience you can give me some suggestions. I highly appreciate your time of reading and answering my question. Warm Regards, Thang Nguyen

QUOTE(ned @ Sep 18 2007, 02:19 PM) Could you tell me more detail about this? I am not clear about why there is the different between the address of the shared variable in modbus slave 4000001 and shared variable in master 400001. What I have tried to do is in the target I create the Modbus Slave Server and 1 variable bind to it. In the host PC, I create the Modbus Master Server and 1 variable bind to it. All of the variable have the same address. I cannot read anything form the variable on the Modbus master. Thanks, Thang Nguyen

QUOTE(ned @ Sep 17 2007, 04:33 PM) I did solve the problem about the shared variables which bind to the modbus. Form the PC, I can read the data through the shared variables already. But when I tried to use a Modbus Simulator to simulate the Modbus Master, I cannot read anything form the same adderss. Because in this project, I use the PI Server to read from the modbus. It's not a VI run on the host machine. I don't know what is the real problem with it, I tried some simulators already. Could you give me some recommendations? Thank you, Thang Nguyen

Hi, I am currently working on a project which require to implement the Modbus Slave in the cFP 2120. +The first thing I know is I cannot use the shared variable bind to modbus because this device does not support modbus (only cFP 18xx). This is confirmed by application engineer of NI. +By searching some forum, I know that we can use the Modbus library inside the FP device. But I am not clear how to lunch the Slave demon VI. Actually I don't know how to use this library in the FP device. Should I add the library as a folder and then use the VIs in this library? I tried to add the MB Ethernet Example Slave into the target, and run the MB Ethernet Example Master on the host PC, but it didn't work. Then I tried to build the RT executable file and deploy it into the FP, and it didn't work either. +By the way, could you tell me how can I change the address of the register in the modbus I want to use ? I highly appreciate your helps, Best regards, Thang Nguyen

QUOTE(Ben @ Sep 12 2007, 09:40 AM) @Ben: Could you tell me what is the format into string VI? I don't know about this . I have to you the property strings[] and array indicator to get the string of an enum. @All: You guys are experts in LabVIEW, so if you have time, it's really helpful if you can list down these tricks in VI. I really want to learn more about these stuffs. It's hot :thumbup: . Thang Nguyen

I tried to create a test project to test the modbus but it doesn't work. Could you help me? In the target, I create a library. After that I create a Modbus Slave I/O Server. Then I create a shared variable bind to this modbus. In Target VI, I write the value to this shared variable. In the host VI, I read data from this VI. The issue is I only get value "1" from this shared variable with watever this shared variable is updated in the target. I attach here all of the necessary images.

QUOTE(ned @ Sep 10 2007, 01:40 PM) Thanks for your recommendation.

Hi, I start working on a project which requires connecting many cFP devices. The requirement is I have to put all of acqusition data in the modbus protocol, so the database of client can access to these data. I have just thought about make each cFP work independentl with modbus server inside and run with deployed real-time program. Each cFP will have a range of data address shared variable. But I don't know that if all of these modbus servers can be combined to become one? I woulk like to ask for your recommendations. This program does not need to be real time. Above is just one idea of mine. I am still thinking right now. Highly appreciate your helps. Best regards, Thang Nguyen

Hi, I have just finished one project in which I implement some class with LabVIEW OOP in the LV 8.2i. When I build the executable file, I meet this error ============================================= An error occurred while building the following file: D:\My Application\Classes\DAQ Control\Private\Internals\GetData.vi The VI became broken during the build process. Open the Build Specification and enable debugging to include the front panel and block diagrams. ============================================= I tried to enable the debug, but I meet this warning: ============================================= A name collision occurred during the build. VIs were renamed to protect the build. If any dynamic calls were made to the following VI(s), unexpected behavior may occur. ============================================= Because in each class I have similar VIs, for example GetData.vi, is it the reason of the warning? Then when the building process come to the last stage, which means I see the message build completed, the LabVIEW start to crash. If someone have any idea, please help me. Highly appreciate your help. Thang Nguyen

I got it. Thank you.

Thank you so much, I have just found myself a really simple way. I just only need to select the property for the path control which browses for the directory only. Anyway, I studied a lot of new techiniques here. Thank you again, Thang Nguyen

Hello, Could anybody tell me is there any way to browse for a directory only? I want to let user select the directory, and write the name of the file seperately. The current Path Control is used only to browse for a file. Behind are two examples I want:

Hi, Could anyone tell me which VI I should use as a control for a supVI, so by which I can pass different typoe of control reference? For example this can be different cluster. I want to make a general VI which can do samething on different kinds of clusters. Thank you, Thang Nguyen

Rolf, I now find out exactly the problem is because of the driver, or UDP protocal. I test the program with only 2 VIs UDP Initialize and UDP Close. I run it for 10 times, then the error happens for 4 to 5 times. I try to modify a little bit with add a delay part into it which very from 0.5 sec to 5 sec. The problem still happens. And the issue happens at the UDP Read -> UDP Read Response -> UDP Get Devices -> UDP Initialize.

Hi Tomi, To build the executable file, do I need to put the process VIs in the Dynamic VIs and Support Files listbox? Thank you,

I still don't know how to solve this problem. In VI, at the first time, I meet the error 54, then after reinitializing, it works fine. But if I run in highlight execution mode, I didn't meet this error. In executable file, at the first time, I meet the error 60, then after re_initializing, I meet the error 6003. I tried to run with your driver, but it still the same. Then, I tried to increase timeout, event, to 1sec. I also add the line: SocketSetReuseAddr=TRUE into the labview.ini file. But it still does not work. Is there anyone have the same problem with me? Waiting for your recommendations. Thank you for your time, Thang Nguyen

QUOTE(yen @ Jun 23 2007, 03:38 PM) I tried to make some changes, but it's still not work. One of the reason lead to this issue, in my thinking, is I use the reference, not connect directly to the plot indicator. Because I use a seperate thread for displaying, so I cannot plot directly on the wavefrom in the main panel. I create an waveform indicator for the thread and it works well. I attach the pictures here. If I let the program run continously, the plot on the main GUI still displays from 2007 to 2110 then more. I use the chart, so the waveform can be updated easily by the parallel thread.

QUOTE(rolfk @ Jun 22 2007, 01:15 PM) Rolfk, Thank you so much, The reason I have to call the open twice because at the first time it cannot open the connection. In my program, I allow user retrive the connection with the device if it cannot open the connection automatically. If the connection does not open, there will be a dialog allow user to call this VI again, then it works. The only problem is it cannot work in the executable file. That make me confuse. Base on your solution, I will try to close the connection before open it. Could you tell me where did you fix in the library or can you remake it in the LabVIEW 8.2? I use LV 8.2.1. Thang Nguyen

Hi, You can take a look at this topic http://forums.lavag.org/CR-Get-Reference-T...rols-t7354.html or for more simple just right click on the object and create reference. Then you can pass this reference and change the value base on the property node. Thang

Hi, My project requires to connect with a Direct Logic PLC base on the UDP protocal. I have the driver for the PLC. The communication is started by initialize the UDP communication and generate a connection ID. If I need to read something form the PCL by using the driver VIs, I need to connect this VI with this connection ID. The program works fine before building executable file. I have normal connection, although I have to initialize the connection with the PLC two times. I think the problem because of the UDP protocal. Then when program runs, I can get all of the data I need. The issuse is after I build the executable file. I cannot initialize the connection anymore. I attach here the error message. I don't understand why there is a different between program run based on executable file and based on compile form the code. Is it the problem with the driver library? I use this VI by open the functions palette, then click select a VI, then browse to the VI in the llb. Please help me on this issue. Highly appreciate your time. Thank you so much, Thang Nguyen

QUOTE(yen @ Jun 22 2007, 06:25 AM) I try to do what you say, but it still not work.

QUOTE(Sherif @ Jun 13 2007, 03:58 PM) Hi, XAxis is the timestamp, so what should I specify for time? I try to put some random number there, then in the program I use property node to set the max and min range to current day/time, but what I get now is from 1997 to 2007?????? I took me quite a lot of time. I cannot understand why this happens. Thank you for your time, Thang Nguyen

Herbert, Thank you so much for your meanful information. I want to confirm this information: Is it always true that storing the Y value of waveform and seperate it with the timestamp is more efficient than storing the waveform? Based on the property of TDMS channel (wf_increment, wf_start_time), I think TDMS naturally used to store waveform. But in this case, it is easier for me to read data out, if I seperate the data and timestamp. Love to hear about this: QUOTE I have never come to Caffee Suoi Da, actually, there are a lot of coffee in Vietnam ( a lot ...). I lived in Saigon. . Do you feel hot there? Thank you again, Thang Nguyen

QUOTE(Herbert @ Jun 18 2007, 01:58 PM) In my program I put store VI into the loop. It scans through the array name of channel, then, read and store the correspondent data into the file in that sequence. That why those channel don't have the same start time. But the diffference is just some msec. I have two questions for you: A) Is the wf_increment depends on the dt? If that is the case, I understand why the data are stored with the same wf_increment. B) Do you mean that I should gather all of the Y value of each channel into an array, then put everything into the TDMS file? Could you tell me more detail how to store everything at once into the TDMS file? Thank you, Thang Nguyen