How better to apply a data serial port FIFO buffer?

Similar Questions

• Serial port receive buffer overflow error

  I am trying to send a file to a folder in my computer to another folder in the computer using conncections tcpip as part of me learning labview. But I get an error

  Possible reasons:

  LabVIEW: Serial Port receive buffer overflow.
  =========================
  LabVIEW: The network connection was refused by the server.

  I don't know how to fix this. So please help me. I have attached the VI here. Thanking you,

  You read just 1 character of the file.  With your read file, on behalf of the value-1 to read the entire file.

  In addition, for writing file, there is a Boolean input on top for 'Prepend/string Size array.  The value FALSE or you will get some additional data at the beginning of your file you want.

• How can I check if a serial port is busy?

  When you use a controller of VISA resource to the list, and then select a serial port, is it possible to check if the selected port is busy (already active in another application) or not?

  To check whether or not the port already open you can also use the WinAPI CreateFile function.

  Also, you can read the following article: Serial Communications in Win32.

  From my point of view by using the VISA functions much easier. Just call VISA set series Port.vi, and if port buzy, then you should receive error code 0xBFFF0072 (the resource is valid, but the VISA cannot currently access). Not understand, why you can't use it.

  Andrey.

• How to periodically send various types of data via the Serial Port?

  Hello! Everyone

  I have to send data to LabVIEW to my device on the Serial Port.

  I know how to send data on serial port in LABVIEW, I already have this part.

  Now the problem is that I have several types of data I need to question my embedded device, if I want to send the query periodically command.

  So lets say that my four Op Codes are the following, which will send four different types of query command to my device on the serial port.

  (To be honest only OP_LED and OP_SENSOR is used now)

  0, OP_SYNC

  1, OP_LED

  2, OP_SENSOR

  3, OP_FUTURE

  Structure of basic package is as follows:

  Header (0x2C), Checksum, length of the data (n bytes), Op_Code (1 byte), length (length of Code + data Op)

  For OP_LED, I need to send the package as follows:

  0x2c 0x02 0x01 0 x 00 0x2F (0x2F being the XOR checksum) (calculation of Checksum part is done and SUB Vi form)

  Length of the package this is 0x02

  0x01 is Op Code for OP_LED

  In the same way

  For OP_SENSORi need to send the package as follows:

  0x2c 0x03 0x02 0x00 0 x 00 0x2D (0x2D being the XOR checksum) (calculation of Checksum part is done and SUB Vi form)

  0x03 is length of packet here

  0x02 is Op Code for OP_SENSOR

  So, how can I do this periodically in labview, in such sort that period can be adjusted whenever necessary.

  Is there something in LabVIEW to do.

  I had done the reception and decoding part and working properly.

  http://forums.NI.com/T5/LabVIEW/store-data-coming-from-serial-port-in-buffer-and-then-take/m-p/32722...

  So I must implement read and write the part of same while loop?

  Do not insert in the table if you put data in an array at index 0.  Just use array to build.

  No need to have Visa to write don't be a part of wire to the wire of reference and error VISA go in the upper part.  These wires should go THROUGH the entry VISA.

  Don't your checksum requires all the bytes up through data?  Righ now, you only put the checksum on data bytes and forget the opcode and length bytes.

  Your sending is not the opcode for Opsync or Opfuture.  You just send the empty tables.  At the same time for the other two, you put the opcode in the data table.  All your original opcode in the table build thread.  Get the data out of these structures in case item which is supposed to represent the opcode.

  xpress_embedo wrote:

  Now it works but I have now two problems.

  (1) OP_SYNC and OP_FUTURE do not data, but still receive its data on serial port, can I do something here as I have nothing when the table is empty in the structure of the case.

  I do not understand this statement.  Perhaps my answer above will fix any issue you have here.

  (2) how can selection operation Code to be send is done using control façade but real application, this task should be automated to a certain frequency, like OP_LED package must go out to the serial port to 100msec and packet OP_SENSOR must go out to 1000msec, I do this.

  Now you agree a little more architecture.  I would encapsulate the code that is in the while loop as a Subvi.  Then with the hand of your program while loop, use two time Express VI, a game for 100 msec, the other for 1000 msec.  When an express VI is true, run the Subvi with a command set waiting for the answer.  When the other VI Express is true, have it run the Subvi with the other set of commands.

  The device responds with anything when you send these commands?  You only send data.  I see no VISA Read to be able to recover all the data.

• How to convert string data from the serial port to double?

  Hello!

  I am very new in LabView and attempt to read data from an OHAUS pioneer pa-313 electronic scale via RS232 serial port. I use the VISA. I can read the data and see it as a string to the screen, but when I try to convert it to a double, it is just the integer and decimal numbers have disappeared. Here's the question: what can be the problem? How can I get the decimals as well?

  What is your normal decimal point?. or?

• How to trace data sent through the serial port by controlling simultaneously the buttons

  Hello

  I want to plot data by controlling the two buttons at the same time and the draw according to my control using communication serial port, but the problem is that the plot on the graph alternates between the two controls his do not change according to my control for example if I move the potentiometres1 / 1000 and button 2 to 4000 replacing these values on the graph I placed a select control, the problem is still not resolved u can help me please thanks in advance

  Regarding

  Samatha

  
  

• read data from a serial port

  Hello to everyone
  I use oracle forms 6i. I want to read data from a serial port. How can I do this?

  HII,

  You may search for any existing OCX or VBX component capable of doing this job.

  Better compliance
  Skyniazi

• Signal output data expressed on a serial port

  Hello everyone,

  I received a task which requires me to collect several channels in express signal analog voltages before displaying these data to the serial port of the computer. My programming experience is very limited as Im working on the back of the high school before going to College, and even though I have the foundations of basic labview stowed, Im struggling to understand how to approach this problem.

  I started looking at the base read the series and write vi provided in the examples and I know how to get labview vi to intergrate with signal on purpose, but because of my lack of knowledge related to the use of channels of communications, binary, hexadecimal and asqui I don't really know where to go from here. The writing and reading of strings for example, I don't understand.

  I would like the data are ideally output on the serial port in real time and data are collected continuously at 6 kHz.

  I realize that there probably is no simple answer to this question, given my lack of knowledge, but any help would be greatly appreciated!

  Thank you!

  Harry

  Hi hcook,

  As smercurio_fc said, the strings that you send are totally dependent on what you're talking about. I haven't used a 'box of dspace' before, but a normal serial device will wait to receive specific orders.  Once it receives an order of some, she will perform a certain task.  You are right in saying that you need to establish what string commands to send to the box of dspace.

  You can find these useful:
  General concepts of Serial Communication
  Overview of Serial Communication

  I hope this helps.

• analysis of the chain of the serial port to retrieve data

  Hi all

  It is a problem of beginner. I have two sensors sending data to a same wireless serial port. In order to distinguish which is which. I coded each sensor to send data with a unique address UoL 000 X, then followed by two values, I want to read. These two values are in the float with format fixed impression (decimal fixed after the third bit). The format string of the first sensor should looks like UoL 0001 123,45678 876.54321. I use the Scan of the String function, unfortunately, it doesn't work that way. Could you please check the VI for me? Or a better solution for this application. Thank you very much.

  S.G

  It does not because what you have set is not different from what you have joined earlier.  Have you tried something?

  See this amendment attached to your VI.  The format strings work with the examples you gave, and sends the data to the appropriate indicator.

  Also, I cleaned up the mess that the inner loop where you were waiting for 1 or more bytes.  Which means most of the time that you would probably get an incomplete message.

• Store data from the Serial Port in the buffer and then take action?

  Hello! Everyone,

  I'm new to LabVIEW and I take assistance from various videos and stuffs available online to get started with LabVIEW.

  But I have a duty, therefore needing help.

  initially I see some of the tutorial videos and learned about the LabVIEW interface, and does a little project to communicate with the Port series (receiving and sending data).

  Happens to my task.

  My LabVIEW application will send a few State request packets on my device or control and based on the response packet that I have to display values.

  The Structure of package is as

  Header, length, Op_Code, data Checksum

  There is no terminator as newline or carriage return or anything else.

  In C language, I read the data from the Serial Port, and based on the length, I conclude that I got the full package or not, and then by recalculating the checksum value, the integrity of the package is verified and then based on that Op-Code has been sent will be decided.

  (I'm dealing with hexadecimal data)

  But how can I do this in LabVIEW.
  A tutorial or any referece will be useful for me.

  1. I suggest that you learn to use Shift Registers instead of local and global variables.  They are much more efficient (memory and execution speed) and make it much easier to read the schema.

  2. you don't need this inside the loop property node.  Is there a way to configure a Serial Port to turn off the stop character.

  3. you don't need to wait for playback VISA will limit the rate of loop if no data is coming.

  4. Once you have the length, you simply read the rest of the entire message and process it at a time.  This will make things a LOT faster.

  5. you should really do this enum a def type so that you can ensure that all your enum constants have the same values.  If you need to add a State later, simply update your enum in the same place then.

  

• Waiting for data on serial port

  Hello everyone.

  I'm trying to figure out how I can solve a problem on LabView. I programmed an Arduino board to read and send a data table of the accelerometer on the serial port. I want to LabView to receive the data and graphs it. My problem is that Arduino send data on an ongoing basis and sometimes LabView can not cope with traffic and read some values "0".

  Is it possible to wait for the data and solve this problem?

  I joined my current vi.

  Thank you much in advance.

  AndreasSchnaas wrote:

  Yes, the characters are 0-9 and - no. ' + 'or'. '. And bytes that vary.

  Once again, thank you very much.

  Given that you send ASCII characters, change your Arduino code to send a character to end of line (10 byte value) at the end of each transmission.  Your code is already configured to use it.  Then you need not use the bytes to the Port at all.  Suffice to say the VISA of reading to read a large number of bytes.  Playback stops when it finds the stop character (value 10).  Your code will get a lot easier from there.

• Using the Serial Port for data acquisition Non-Serial

  I searched the forums and can't find anything on this topic.

  I saw that it was possible to use the parallel port for e/s digital single and I was hoping that the serial port can be configured the same. It seems all VI VISA only to use the serial port to receive ASCII characters at a given flow rate, but is it possible to simply query the status of the line series at my own speed to see if it is high or low, kind of like a single pin DAQ?

  It seems that it would be possible until the serial data are read and controlled by labview, not Windows. Let me know if you have ideas of how to approach this problem, or any comment as to why it is not possible.

  Thank you all!

  Select the property > settings series > Modem of the line parameters. For example, the State of the CTS is an entry to the pc.

  With the help of these lines is a very poor substitute for a scope or map DAQ. The only things you can return is Asserted, Unknown or Unasserted. The range of acceptable signals is important enough. Anything between + 3 and -3 is an unknown state. Your other signals is + / 3 to 15 volts. What type of signals do you really want to capture?

  Edit: there is no such thing as a visa so I have no idea of what you actually use.

• How to read a serial port?

  Hello

  I am a complete newbie to Labview and hoped that one of the benefits could point me in the direction of a tutorial on how to acquire data from a serial port. I downloaded some programs here, but I really have no idea of what is happening in their. I also tried looking for the tutorial and through the forums, but all I've found is too specific and would really like to know how to go about reading data.

  Thank you!

  Search for series in the Finder for example of NOR (help > find examples) then choose the basis series write and Read.vi.

• How to transfer files from PC to PC via a serial port using labview

  I need to transfer files (.txt, .doc, .xls) from PC to PC via a serial port using LabVIEW. Is it possible to transfer files, if so how to transfer?

  Yes, it is possible to transfer files with the serial port using LabVIEW.  The files are just collections of bytes and the serial port is good enough in the expedition of the bytes from one PC to another.  You must connect the ports series with a null modem cable.

  First, take a look at the example of serial communication.   In LabVIEW, go to the Help menu and select «Find examples...» ».  From there, you can search for "serial" or navigate to hardware input and output > series.  Select «Write series base» and Read.vi  Try this example to gain confidence on the serial communication methods.

  Then it's time to learn how to read and write files.  For this, the examples might be somewhat confusing as they deal with files that are presumed to have data of a specific type in them.  I would recommend just familiarize yourself with the functions in the file e/s palette.  Specifically, familiarize yourself with the following functions.

  1. Open/create/replace file - on the side of your destination, you will need to create the copy of the file you are trying to transfer
  2. Close the file - when you're done reading or writing to a file, you must close it.  It cleans the memory used and finalizes write operations that are still floating in the write buffer.
  3. Read a binary file - is the best way to play a file when you don't really like what type of file it.  In your case, you just want to get these read bytes and sent so they can be written down instead of destination.
  4. Write to a binary file - next to the destination, is what will store the bytes in the file that you created with the number 1.
  5. Size of the file get (under the range of the advanced features of file) - you need to know how big the file is, so you know when you are finished.

  OK, so once you are able to create files byte write and read bytes from existing files, you can move forward.

  I suggest the basic method is to have the user specify a source file on the source PC, and a folder on the destination computer.  Then find the size of the source file using the number 5.  Divide this number of size by the number of bytes that you want to transfer to the times.  The series pads are usually around 32 k (if I remember correctly) in order not to exceed that.  Now start to send data by reading a number of bytes and this string output wiring to the feature of writing VISAS.  On the side of destination, you will want to monitor the serial port for bytes and read when they arrive.  This string of yarn to the writing of the function of binary file to add them to your destination file.

  This is the basic outline of how to do it.  He needs to not to overload him write and read buffers on the serial ports.  Initially, you can use delays on the side sending to make sure that the side reading has enough time to digest.  To make things faster, you can bring in a control of flow.

  If all that sounds a little intimidating, there are there Alliance member companies (such as the automation of PrimeTest) who can write this code for you and even provides a turnkey for you solution.

  Happy wiring,

  Dan press

  Certified LabVIEW Architect

  PrimeTest Automation

• Select the project of the serial port data

  Hello world

  The project aims to use labview to receive data from a serial port wireless. The serial port will receive two values (X 1 and X 2) every 10 minutes. I want to use these two values as inputs to my formula. How to make the selection? Thank you very much.

  Baicy

  Scan from a String.

  Using the first option and put numbers for zeros so that it shows some kind of significant result.