NO EOF in Labview 8.0?

Hey All:
I read some earlier discussions on the use of an End Of File (EOF) function from the functions pallette. I am using LV 8.0 and I cannot for the life of me find an EOF Function in the 'advanced file functions' pallette.
Has it been eliminated or replaced in LV 8.0?
Thanks in advance!
Phil

Hi Phil,
Page 14 of the LabVIEW Upgrade Notes ([labview]\manuals\LV_Upgrade_Notes.pdf) says "In LabVIEW 8.0, the EOF function is not on the Functions palette. Use the Get File Size and Set File Size functions instead."
Hope this helps,
-D
Darren Nattinger, CLA
LabVIEW Artisan and Nugget Penman

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How can I set delay time to POST on tcp/ip

I tried to convert to Labview from PHP below source.
but I couldn't check EOF on Labview as php source.
function http_post($host, $path, $data)
$http_response = '';
$content_length = strlen($data);
$fp = fsockopen($host, 80);
fputs($fp, "POST $path HTTP/1.1\r\n");
fputs($fp, "Host: $host\r\n");
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Attachments:
tcp_post.vi ‏28 KB

Hello mostech,
I, personally, am not very familiar with PHP, but I am somewhat familiar with ASP, http, etc. (Same idea, different language). From the code you posted, it looks like you are just trying to read the HTTP response from whatever server you are posting data to. To do this in LabVIEW, you will use TCP Read; and rather than constantly checking explicitly for the EOF, you can let the TCP Read error out. In other words, keep calling TCP Read in a while loop (like you have in your PHP code), and make the stop condition be a TCP Read error.
I found an example program on our website submitted by another customer. It looks like it is doing something similar:
Example HTTP Protocols
http://sine.ni.com/apps/we/niepd_web_display.display_epd4?p_guid=CA9910104C671493E034080020E74861&p_...
Hope this helps!
Charlie S.
Visit ni.com/gettingstarted for step-by-step help in setting up your system

LabVIEW for ARM 2009 Read from text file bug

Hello,
If you use the read from text file vi for reading text files from a sdcard there is a bug when you select the option "read lines"
you cannot select how many lines you want to read, it always reads the whole file, which cause a memory fault if you read big files!
I fixed this in the code (but the software doesn't recognize a EOF anymore..) in CCGByteStreamFileSupport.c
at row 709 the memory is allocated but it tries to allocate to much (since u only want to read lines).
looking at the codes it looks like it supposed to allocated 256 for a string:
Boolean bReadEntireLine = (linemode && (cnt == 0));
if(bReadEntireLine && !cnt) {
  cnt = BUFINCR;    //BUFINCR=256
but cnt is never false since if you select read lines this is the size of the file!
the variable linemode is also the size of the file.. STRANGE!
my solution:
Boolean bReadEntireLine = (linemode && (cnt > 0)); // ==
if(bReadEntireLine) {    //if(bReadEntireLine && !cnt) {
  cnt = BUFINCR;
and now the read line option does work, and reads one line until he sees CR or LF or if the count of 256 is done.
maybe the code is good but the data link of the vi's to the variables may be not, (cnt and linemode are the size of the file!)
count should be the number of lines, like chars in char mode.
linemode should be 0 or 1.
Hope someone can fix this in the new version!
greets,
Wouter
Wouter.
"LabVIEW for ARM guru and bug destroyer"

I have another solution, the EOF works with this one.
the cnt is the bytes that are not read yet, so the first time it tries to read (and allocate 4 MB).
you only want to say that if it's in line mode and cnt > 256 (BUFINCR) cnt = BUFINCR
the next time cnt is the value of the bytes that are not read yet, so the old value minus the line (until CR LF) or if cnt (256) is reached.
with this solution the program does not try to allocate the whole file but for the max of 256.
in CCGByteStreamFileSupprt.c row 705
if(linemode && (cnt>BUFINCR)){
cnt = BUFINCR;
don't use the count input when using the vi in line mode. count does not make sense, cnt will be the total file size. also the output will be an array.
linemode seems to be the value of the file size but I checked this and it is just 0 or 1, so this is good
update: damn it doesn't work!
Wouter.
"LabVIEW for ARM guru and bug destroyer"

Reading in data from a file and terminating at EOF

Hey all,
Im relatively new to labview so this may seem to be a simple question. My task is to read in a file with integers with "n" lines, until the end of file. I only need to read in the first 3 numbers of each line. Right now my code works for only one line of code, but when I try looping to iterate "n" lines, it gets stuck in an infinite loop. I am not sure how to make the while loop end at EOF. Any suggestions would be helpful. Thanks!
-Micah

I'm with Jeff. By far the easiest way is to just read the whole file and use the Spreadsheet String to Array function to get all of the data into a numeric array. You can then just use Index Array or Array Subset to get the values you actually care about.
There are only two ways to tell somebody thanks: Kudos and Marked Solutions
Unofficial Forum Rules and Guidelines

VISA issues when switching from Labview 5.0 to 8.5

Hello all
I am using a pressure transducer that I read using RS-232. In Labview 5.0 I used the Read Serial VI and it worked with no issues (I also tested it with the VISA from 5.0 with no problems either). Now I have upgraded to 8.5 and I seem unable to communicate with it anymore. The usual error I get when i try to read is a timeout error.
I ran the Troubleshooting Serial Line Monitor VI and it seems to work (RI blinks when the output lines are off, DCD RI and CTS blink when DTR is on, and RI DSR and CTS blink when RTS is pushed) The Basic Read and Write VI does not work however. Whenever I get bytes at port it always returns 0. I am using a USB-RS232 converter but this problem remains when I tried using an RS232 port on another computer running 8.2.
I recently added the VISA 4.3 drivers but this did not help.
Thanks for any ideas.
Thomas

This morning I tried with both the DOS prompt and Indigo terminal emulator. I also checked the setting on my manometer and the manual says that the settings should be:
Baud Rate: 9600
Parity: None
Auto Line Feed: Yes
Margin: 0
Decimal Point: "."
Send EOF: Yes
I then followed the instructions to set the port with MODE COM5:9600,N,8,1,P and it returned
transfer rate: 9600
parity: none
databits: 8
stop bits:1
timeout: on
XON/XOFF: OFF
CTS-handshaking: ON
DSR-handshaking: ON
DSR-sensitivity: OFF
DTR cycle: Handdhake
RTS cycle: Handshake
Then when I try to log the data with COPY COM5 log.txt it creates a txt file on my desktop with no information.
I checked the parameters on the old Labview 5.1 (not 5.0 as I said earlier) computer and they were
Error Replacement Character: 0
Flow Control XOFF Character: 0
Flow Control XON Characcter: 0
Serial Baud Rate: 9600
Serial Data Bits:8
Serial End Mode for Reads: Term Char
Serial End Mode for Writes: None
Serial Flow Control: None
Serial Parity: None
Serial Stop Bits: 1.0
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With 8.5 I got all the same except
End Mode for Reads: None (when I changed it to TermChar, it didn't help)
XON: 17
XOFF: 19
There were many many more modem line settings but I didn't include them because they weren't in Labview 5.1

How can I use LabVIEW to send the equivalent of a CTRL D (in VT 100 format) out the serial port of my computer?

I am trying to write a vi that interfaces with a piece of OEM equipment that is set up to talk with a VT 100 terminal. I can't seem to locate the ASCII equivalent string (if there is such a thing) of a CTRL D. Is there a vi that emulates VT 100 commands?

If I recall, CTRL-D is EOF on most ASCII tables.
You'd probably have to use an escape sequence
or if you can use an unsigned 8-bit that might be
easier.
In article <[email protected]>, TLS
wrote:
> How can I use LabVIEW to send the equivalent of a CTRL D (in VT 100
> format) out the serial port of my computer?
>
> I am trying to write a vi that interfaces with a piece of OEM
> equipment that is set up to talk with a VT 100 terminal. I can't seem
> to locate the ASCII equivalent string (if there is such a thing) of a
> CTRL D. Is there a vi that emulates VT 100 commands?

How does labview detect end of file?

Hello!
My question is how labview detects the end of file at the Read from Spreadsheet File VI. What I would like to do is basically to read from a text file a number of numeric values and afterwards build an array containing these values. Till now I have made a vi that uses the aforementioned vi and put it in a while loop that its conditional terminal is connected to the EOF? but it never stops. Could you please suggest a solution to my problem? (I have already seen a similar question in this forum but the answers didn't help me..) The VI along with an example file to read are attached.
Thank you very much
Attachments:
readfromfile.vi ‏9 KB
Book1.txt ‏1 KB

Please take off the while loop. and directly connect the indicator to the all rows output of the VI.
That will give you a 2D array of whatever is there in the spreadsheet.
Hope this helps.

Reverse Engineering Portmon log to obtain Labview serial configuration settings

Hi there,
I am attempting to interface Labview with a custom-designed power supply device through a USB-RS232 adapter. The power supply came with a "debugging interface" programmed in java with which one can send and recieve commands to the board (detect, set voltage, get voltage, stop, reset, etc.) through the USB-RS232 adapter which works fine.
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Nonethless I've tried the advanced serial communication example provided by NI, (http://www.ni.com/example/27665/en/) - I have appropriately set to COM3 as my device manager (and MAX) find the correct port for the device, baud rate, data bits, stop bits, parity, flow control, XON/XOFF characters, Input Buffer Size, End read/write with termination character, which termination character, and how long till time out.
Yet from my Portmon log, I'm seeing that the java interface sets a few other parameters that I (at the moment) do not have access to through the labview VI (or from MAX). How do I set Output Buffer Size? What are EOF? EVT? Replace? XON/OFF limits? WC? How do I set them?
Both Portmon log files are attached.
Attachments:
javaserial device config log.txt ‏4 KB
configlabview.LOG ‏6 KB

Output Buffer Size - This is set with the VISA Set I/O Buffer Size VI that is in the example you were looking at. The documentation says it is just the Input buffer size but it is actually the I/O buffer size.
This forum post answers your question about XON/OFF Limits:
http://forums.ni.com/t5/LabVIEW/Can-I-set-XonLimit-and-XoffLimit-for-serial-port-communication/td-p/...
I am not sure yet about the other commands you have asked about. Have you looked around in the VISA Serial property node options? Have you made any progress?
Applications Engineer
National Instruments

Labview Binary Data

I have written some C programs for signal processing. I need to adapt
these programs to accept binary data acquired by a colleague using
Labview.
The colleague mentions that the data is a 2-D array with a time column
and an amplitude column. Furthermore, the the data is stored in 64-bit
IEEE double precision format.
Can anyone tell me how to read this data format into a C program?
Thank you.
Sincerely, Tom Irvine
[email protected]
Sent via Deja.com http://www.deja.com/
Before you buy.

In article <823irg$inb$[email protected]>,
[email protected] wrote:
> I have written some C programs for signal processing. I need to adapt
> these programs to accept binary data acquired by a colleague using
> Labview.
>
> The colleague mentions that the data is a 2-D array with a time column
> and an amplitude column. Furthermore, the the data is stored in
64-bit
> IEEE double precision format.
>
> Can anyone tell me how to read this data format into a C program?
>
> Thank you.
>
you could read your data and convert them into the standard 2D array.
The 2D array can be as a input of your CIN.
Of course you need to know the saving format of your partener's file.
Then, if I were you, I would just simply use the I/O function in Labview
--open, read, close..plu
s a while loop to index your read data to a 2D
array... the loop will end by the EOF. Note that you need to "read"
your data is dbl-precision by specifying the "data stream type"
parameter as double-precision data. (Simply right-click the "data stream
type" input and click the "creat constant" in the pop-up menu).
It's simple and neat. I've done several this kind of work..even some
with complex data structure.
Luck,
G. Chen
Ph.D. Candidate
Ohio Univeristy, Athens, OH
Nothing can dim the light which shines from within.
Sent via Deja.com http://www.deja.com/
Before you buy.

I need to scan an input string for EOF (control Z) and then view the data that has come in since the last EOF.

I'm talking to a Furness micromanometer. It sends a string of three lines formatted as follows:
Time                 xx:xx:xx xM
Velocity            xxxxx ft/m
Temperature    xxx.x degC
I want to watch the input, and when I see the EOF character (ctlZ), I want to display the three lines of text sent since the last EOF. Any help is appreciated.

Lynn, attached is the original vi I wrote months ago. It works, but occasionally there seems to be a disconnect between the instrument and LabVIEW. The string received is shown in the upper left corner of the front panel (Micromanometer output) is the string last received. Then it's parsed out into teh three columns. AS you can see from the block diagram, I made a rather complex vi, although that was NOT my intent. Occasionally, as I said, things don't work right. Instaed of the first line beginning with "Velocity", it might read "city" and then everything is sort of offset, and the data is corrupt. After closing and reatarting LabView it usually works correctly. SO, I decided to go with a simpler, less complex approach. Instead of sending the T to the instrument to trigger it, I simply set the Furness to sample at one second intervals (locally - on its front panel interface)and send its data out on the serial port. Then I want Labview to monitor the port, and read the data whenever it sees there is date to read. I don't know if I can use EOF or the start bit, or what. I just wrote an application like this for another instrument, but I was able to determine the number of bytes in the string (19). I just used a property node (Bytes at port), compared the numer to 19, and if it was greater than or equal to 19, I read the port. It works great, but I can't seem to get a handle on what I'm doing wrong here. Anyway, attached is the old vi, as well as the beginning of the new one. Help??!!!
Attachments:
Furness.vi ‏291 KB
simple.vi ‏75 KB

Como Funciona EOF

Quiero saber, en un archivo de texto, donde es donde termina, para poder escribir después de lo que tiene, y no sobreescribir información.
Pensé que tal vez sea con el bloque EOF, pero no se bien como usarlo, mi problema es con el refnum, como le hago para indicarle cual archivo es? les adjunto mi VI, para ver si me pueden ayudar
Attachments:
EOF.vi ‏12 KB

Hola Fercho8
El problema es que no estás abriendo el archivo antes de intentar leerlo o accediendo a información en el mismo. Te envío un ejemplo de como se puede obtener el tamaño de un archivo de distintas formas, pues varios vi´s de LabView proporcionan esa información.
También revisa los ejemplos que se encuentran en la ayuda de LabView en Help>>Find Examples..
Saludos y que tengas un excelente día
Attachments:
EOF 7.1.vi ‏26 KB

Problem handing EOF (End of File)

Hello Everybody,
I am new to Labview and I want to read one text file and do some analysis on it. For the same I have developed one .vi which is marking error code4, which I believe has something to do with EOF.
I would appreciate if somebody can help me solving this problem.I have also attached the vi file I am using.
Thanks & regards
Janit
Attachments:
Analysis_1.zip ‏63 KB

Please find attached one typical file.
thanks
janit
Attachments:
book11.txt ‏1 KB

VI isn't a valid labview file

Hello,
i had a computer crash yesterday evening during the development of a VI.
Now, i can't open the VI any more. Labview generates folllowing error :
LabView : End of File (EOF) found. The file "ChangeDevice.vi" isn't a valid Labview File.
The file seems to be corrupt. Somebody knows if i can recover the file ?
Thanks for help

Woully,
Sorry - I can't help you. But - I wanted to add that the same thing happened to me last month
when the computer hung when I turned a PXI chasis back on while the PC was running. I know
now that is not the right sequence. Anyway - my "myname.vi" VI continuously prompts me to
find "myname.vi" when I open it. I was lucky and had a backup copy from the day before,
so lost only one day's work.
I downloaded some file recovery utilities and went searching for left over file pieces - but found
none. This suggests to me that LabView overwrites the existing file rather than making a new
file then renaming the old - as I often do when developing robust file handling protocals.
I am using LV 7.1.1
Mike
"woully" <[email protected]> wrote in message news:[email protected]..
>Hello,
> 
>i had a computer crash yesterday evening during the development of a VI.
>Now, i can't open the VI any more. Labview generates folllowing error :   
> 
>LabView : End of File (EOF) found. The file "ChangeDevice.vi" isn't a valid Labview File.
> 
>---------------------------------------------
> 
>The file seems to be corrupt. Somebody knows if i can recover the file ?
> 
>Thanks for help
Posted via a free Usenet account from http://www.teranews.com

When is EOF moved?

Hi,
I have a Labview 6.0 application which writes a packet (using Write File) of ~1,000 bytes, 100 times a second, to a hard disk on another computer (the drive has been mapped to a local drive using Windows). I have another application on the remote computer which polls the file, looking for the EOF marker to move, indicating a new packet has been written. When the marker moves I read in a packet using Read File. Occasionally I see the EOF marker move a packet's worth, but when I read in the packet it is all 0's. This problem seems to occur less often (but it still occurs) if I use Flush File after Write File, or if I put in a small delay between seeing the EOF marker move and calling Read File. Is it possible that Labview (or Windows) is moving the EOF marker before it has written the data? Is there a way to know when the data should be valid?
ThanksMessage Edited by Phamton on 05-25-2005 04:35 PM

Hi Phamton,
You could implement some TCP handshaking between the two programs to communicate when the file has been updated, etc. This would be a lot more robust than just polling for movement of the EOF character, and it would eliminate the possibility of a race condition occurring when polling the position of the EOF character while the file is being updated.
Hope this helps,
Travis H.
LabVIEW R&D
National Instruments

Improper functioning of LabVIEW vi

This isn't a specific question I'm having trouble with, but more of a curiousity thing.
I was using the Waveform File I/O vi's provided with LabVIEW, but had
very limited success, since I kept getting weird errors. I ended
up making them work properly (to what I thought they would have been
set up for in the first place), by going in and editing a few of the
sub vi's.
I guess my question is, are these vi's editable for that reason?
Or is their functionality limited for some reason I'm not aware of? Am I using them in the wrong way?
For instance, I added the "EOF?" to the connector of "Read Waveform
from File". I would have thought this to be included orignally,
as it's a very important variable (how else would you know when you've
reached the end of the file?).

Novatron wrote:
I guess my question is, are these vi's editable for that reason?
There are many good reasons to have them editable, but as Ed said already, you NEVER want to modify system VIs. You would break everything else that depends on the original functionality and next time you upgrade LabVIEW, you're back to square one.
It is a fantastic learning tool to inspect vi.lib VIs and we have to thank NI that most are not password protected. They're typically (not always) well written and you can use them as a starting point for your own VIs, which you then save elsewhere for future use. Make sure you give them a different icon for clear distinction. I often keep the same icon, but change the background color. For example, many years ago I modified the "write to spreadheet file" so it overwrites existing files without asking questions. I made the icon backround red (because it is more dangerous to use), saved it as "rambo write to spreadsheed file" and placed it in user.lib.
LabVIEW Champion . Do more with less code and in less time .

NO EOF in Labview 8.0?

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