Acquiring two signals and saving at a Table

Good Morning,
I'm new to LabVIEW, and I need help at a Data Acquisition. Let me explain it, so I hope you guys can help me.
I need a graph, and a Table displaying two signals acquired at a Field Point conection: Pressure and Temperature.
At this measurement, I need the VI to measure every five minutes, during one minute every measure.
And I need to save the signals to '.txt'.
I need the Table to save both signals, and a "cronometer', to keep in control of any existant difference in the signals, observing the exact time the signals changed, if it changes.
Sorry for the bad English, I'm an aprentice, using the User of the Area's Supervisor.
Thanks.

Check out the examples that ship with LV you will find something to get you started. Then if you have specific problems we can help more.Mike...
Certified Professional Instructor
Certified LabVIEW Architect
LabVIEW Champion
"... after all, He's not a tame lion..."
Be thinking ahead and mark your dance card for NI Week 2015 now: TS 6139 - Object Oriented First Steps

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Attachments:
separate.png ‏37 KB
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I read DAQmx help and what I know is that Each row corresponds to a channel in the task. Each column corresponds to a sample from each channel.
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Hello Dani,
I assume, based on your position sensors and the image you posted, that you are using counters to acquire your data. Is this correct? If so, it is important to note that you cannot add multiple counter operations to a single task because they have different timing requirements and all channels in a single task must share the same timing and triggering. In fact, if you attempt to add a second counter channel to a DAQ Assistant for a counter operation, you will receive the following error when you try to close the configuration window:
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KnowledgeBase 1JPES6LL: How Do I Synchronize a Buffered Quadrature Encoder Measurement to a Signal
KnowledgeBase 3GGATSCC: Hardware Counter Start Trigger for Counter Synchronization
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Let us know if you have any other questions about taking position measurements.
Message Edited by Matt A on 04-09-2008 03:55 PM
Matt Anderson
Hardware Services Marketing Manager
National Instruments
Attachments:
Error -200147.jpg ‏32 KB
Example Finder Position.jpg ‏124 KB

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We are currently working with these interfaces and other reference examples on the NI site. Unfortunately we cannot seem to properly integrate the code for our system. Does anyone know if this setup is even possible? Also, if anyone has any experience with similar systems and can offer advice, code snippets, or any other assistance it would be greatly appreciated.
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Thanks for any help, it's much appreciated.
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Thanks,
Taylor S. Amarel
Learning is living.
Co-Founder and CEO of http://3dprintingmodel.com/
"If we did all the things we are capable of, we would literally astound ourselves."
-Thomas Edison
Attachments:
Two Camera Avicap32.dll.zip ‏84 KB
USB Capture Example.zip ‏17 KB

Thanks for the information but that's not exactly what I'm looking for. I've been to that URL and read the information before. I don't mean to disparage you help but I'm looking for ways that I can successfully implement a functional system, not information on an unfunctional method. Maybe I was unclear before, I'm looking for any advice, knowledge or help on how to make this system properly work.
Thanks, have a great day.
Taylor S. Amarel
Learning is living.
Co-Founder and CEO of http://3dprintingmodel.com/
"If we did all the things we are capable of, we would literally astound ourselves."
-Thomas Edison

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Hi,
I am acquiring ECG signal wirelessly and displaying it in in waveform chart. And simultaneously i need to save it in Text format for 5 mins. The problem i am facing is that for saving the signal i am using Write to Measurement File which saves the file in text format..... but while saving the plotting speed decreases.
i am very new to labview.. so plz can any one tell me whether i am missing any thing in it... plz help.....

Why do people always post pictures of their VIs rather than the VIs themselves or at least Snippets? We can't tell from the picture what Version of LabVIEW you are using (so if we post code, you might not be able to open it), and we can't "play with" your code and try it out without, ourselves, by hand, trying to recreate it from your (sometimes very tiny) diagram. Please Help Us to Help You!
Here's help anyway to get you started with the Producer/Consumer Design Pattern.
Open LabVIEW.
Click "File", choose "New ..." (not New VI), and choose (from the templates) Producer/Consumer Design Pattern (Data).
Study the Template and adapt it to your problem.
The Producer would be anything that Generates data. Once you have the data, you put it on the Queue and send it to the Consumer for all the rest of the processing. The idea is that the Producer has an inherent timing that it has to meet, otherwise you lose data points. The Consumer, on the other hand, just needs to "more or less" keep up (actually, the Queue can/will expand, so if the amount of data isn't megabytes, the Consumer can really be quite slow, though you usually want the Consumer, on average, to be at least as fast as the Producer).
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The program uses a boolean as a start trigger for the acquisition process. In this manner when the data begins saving(i.e. the boolean is switched) it would send one analog pulse per iteration of the save loop. Unfortunantly I only seem to be able to either send a continuous pulse that I start before the acquisition begins or am not able send any pulse. During the time this pulse is being sent I am also constantly acquiring data from the card. I was wondering if there is any way that I can have the pulse start and initialize before the loop begins and then have it send one analog pulse of a set frequency every time the loop is iterated. I have tried both DAQmx and DAQ traditional solutions but have had no success.
Hardware: PCI-6071-E and BNC-2110 boxes, so I have a large selection of ports and my card seems to be compatible with all the latest software capabilities.
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~Matt

Actually after tinkering with it for several hours I managed to figure out a way to solve my problem. I'll explain it in case anyone else has a problem.
What the software does: The software is an acquisition loop that outputs a square wave pulse of finite frequency to another acquisition system at the beginning of each acquisition iteration while data is being saved. This is so that the data from the two systems can be synchronized later.
The program flow is this Send Single Synchronization Pulse-> Acquire Data->Calibrate Data->Save Data to file->Repeat
The pulse is triggered once data begins saving, but the device begins acquiring data on execution of the software.
To do this I set up the DAQmx Channl configuration to CO Pulse frequency. I then set the timing up to be finite iterations and the number of iterations to 1. Inside the acquisition loop I enclosed the whole acquisition process in a flat sequence. In the first sequence, if the program is saving data it turns the pulse on, if not saving the task passes through. The acquisition occurs in the middle sequence and in the final sequence if saving the task is turned off. If not saving the task passes through. This allowed me to send one pulse of a finite frequency every time the loop is run.
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Hello,
I am quite beginner in Labview.
I want to send a signal to a loudpeaker and acquire the signal of a microphone and a photomultipier.
I have already done the VI to acquire and record, and the VI to send the signal to the loudpseaker.
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I use labview v.8

These is my two VIs.
Moreover when I open and run the sinewavegenerator end then want to run the VI " pm+micro record" the error 50130 occures.
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Attachments:
micro+pm record.vi ‏106 KB
sinewavegenerator.vi ‏161 KB

How can i compare two databases and their tables

i have a text.txt file then
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db_header has tbl_pcountheader with fld_Rack_No(char) PK and fld_DateAdded(date) PK
db_details has tbl_pcountdetails with fld_Rack_No(char) PK, fld_Barcode(char) PK and fld_Quantity(int)
then i will lookup in db_products
db_products has tbl_products and tbl_barcodes
tbl_products has fld_ItemCode
tbl_barcodes has fld_Barcode and fld_ItemCode
now i want to make a prompt contains
Rack No: Date:
Counter No:
Barcode | Item Code | Item Description | Quantity
how can i fill up this by comparing db_details and db_products?
Private Sub bt_upload_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles bt_upload.Click
If saveCheckBox.Checked = False Then
MsgBox("Please click the box to continue.")
Return
End If
If lb_file.SelectedItem Is Nothing Then
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Dim filePath = lb_file.SelectedItem.ToString
' Verify that the file was not removed since the Browse button was clicked.
If System.IO.File.Exists(filePath) = False Then
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Dim fileInfoText As String = GetTextForOutput(filePath)
'LookUP db_header, db_details and db_products
Dim cs As String = "Database=;Data Source=localhost;" _
& "User Id=root;Password=1234"
Dim conn As New MySqlConnection(cs)
Dim ds As New DataSet
Dim da As New MySqlDataAdapter
Dim cmd As New MySqlCommand
Dim dt As New DataTable
Dim stm As String = "SELECT tbl_pcountheader.fld_Rack_No, tbl_pcountheader.fld_DateAdded, tbl_pcountdetails.fld_Barcode, tbl_products.fld_ItemCode, tbl_products.fld_ItemDesc, tbl_pcountdetails.fld_Quantity FROM db_header.tbl_pcountheader INNER JOIN db_details.tbl_pcountdetails ON db_details.tbl_pcountdetails.fld_Rack_No = db_header.tbl_pcountheader.fld_Rack_No INNER JOIN db_products.tbl_barcodes ON db_details.tbl_pcountdetails.fld_Barcode = db_products.tbl_barcodes.fld_Barcode INNER JOIN db_products.tbl_products ON db_products.tbl_barcodes.fld_ItemCode_fk = db_products.tbl_products.fld_ItemCode GROUP BY tbl_pcountheader.fld_Rack_No, tbl_pcountheader.fld_DateAdded ORDER BY tbl_pcountheader.fld_Rack_No"
ds = New DataSet
Try
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da = New MySqlDataAdapter(stm, conn)
da.Fill(ds, "tbl_pcountheader")
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Select header.HeaderText).ToArray
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Where Not row.IsNewRow _
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here's my final code that solves my problem.
i just make the environment of vb into mysql console
so that i can call all the database that i wanted.

Private Sub bt_upload_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles bt_upload.Click
If saveCheckBox.Checked = False Then
MsgBox("Please click the box to continue.")
Return
End If
If lb_file.SelectedItem Is Nothing Then
MessageBox.Show("Please select a file.")
Exit Sub
End If
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Dim filePath = lb_file.SelectedItem.ToString
' Verify that the file was not removed since the Browse button was clicked.
If System.IO.File.Exists(filePath) = False Then
MessageBox.Show("File Not Found: " & filePath)
Exit Sub
End If
' Obtain file information in a string.
Dim fileInfoText As String = GetTextForOutput(filePath)
'LookUP comparison db_details to db_products
'Dim connString As String = "Database=db_products;Data Source=localhost;" & "User Id=root;Password=1234"
'Dim conn As New MySqlConnection(connString)
'Dim cmd As New MySqlCommand()
'Try
' conn.Open()
' cmd.Connection = conn
' cmd.CommandText = "SELECT Database1.dbo.TableName.ColumnName, Database2TableName.Name, 'The reason why Database 2 isnt defined is the fact that it has been defined in the connection" _
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' Database2TableName2 INNER JOIN _
' WHERE (Database1.dbo.TableName.ColumnName = '')"
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'fileInfoText.print()
If saveCheckBox.Checked = True Then
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Dim bakFolder As String = System.IO.Path.GetDirectoryName(filePath)
Dim bakFilePath = System.IO.Path.Combine(bakFolder, "back-up.bak")
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My.Computer.FileSystem.WriteAllText(bakFilePath, bakText, append:=True)
'My.Computer.Network.UploadFile(bakFilePath, "C:\Documents and Settings\SAPC-TECH\My Documents\back-up file.bak", "", "", False, 1000)
'My.Computer.FileSystem.DeleteFile(bakFilePath)
Form2.Show()
End If
'Note: This message box shows that you've uploaded a file and back up it.
MessageBox.Show("Already backed-up to ")
Else
Me.Close()
Application.Exit()
End
End If
Me.DialogResult = System.Windows.Forms.DialogResult.Cancel
Form2.Close()
Me.Close()
End Sub
here's my code wherein i have to compare the two database and save it into .txt file
i just have to get this items
Rack No:
Date:
Counter No:
Barcode:
Item Code:
Item Description:
Quantity:
as a prooflist to be print out.

I need to acquire impulsive signal(s) and then write them to a file - but I need a good approach

Okay, I am pretty new to Lab View, and would appreciate suggestions of how to approach a problem.
My
only LabView experience has been writing a simple .vi to acquire
voltage signals in a loop at a certain sample rate, get 5 of them each
time the loop iterated (it did so every second), average the 5 samples,
and dump them into a file at every loop iteration.
That
was for continuous data acquisition while viewing/monitoring the data
at the same time, and was probably not the most efficient way (or even a
good way) to do it.
Now,
I am doing something different. I want to record voltage signals but
only after a trigger event has occured, and only until a certain time
window after the trigger event.
Should I use continuous data sampling?
Or should I sample "N" samples?
Should I use "producer / consumer" structure?
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Why is the signal at my home so much weaker than it was when I moved here in February 2013? I get only one or two bars and very poor data service if any at all. Calling to ask the question results in a vortex of questions that have little to do with the problem and no resolution or answer.

I have a Droid Ultra phone. The signal reduction seems to only be in the general area of my home. If I go downtown, the signal improves to what it once was at home. Everything at my home is as it was when the signal was good, including cable TV service. There has been no new construction in the area that I know of.
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Hi All,
Is it possible to capture from two tables (master and child table) and apply in one table?
For example,
1. DEPT and EMP tables in source database with relation
DEPT table structure is like DEPT_ID, DEPT_NAME, LOC_NAME
EMP table structure is like EMP_ID, EMP_NAME, EMP_DOJ, EMP_SAL, DEPT_ID
2. EMP_DEPT_STAGING in destination database
EMP_DEPT_STAGING table structure is like EMP_ID, EMP_NAME, EMP_DOJ, EMP_SAL, DEPT_ID. DEPT_NAME, LOC_NAME
if there is any update in DEPT table, EMP_DEPT_STAGING should get populated with Department and its employee details. Similarly, if there is any update in EMP table EMP_DEPT_STAGING table should get populated with Employee details and along with department detail.
Is it possible to accomplish this? If yes, could you please provide me some examples?
Thanks & Regards
Thiyagu
Edited by: mt**** on Sep 4, 2011 11:22 PM

like this
INSERT @PlantNew (PlantID, PlantName, PlantDirExists, PlantAssistantDirID, PlantDirID)
SELECT p.PlantID,
p.PlantName,
CASE WHEN pd.PlantID IS NULL THEN 0 ELSE 1 END,
PlantAssistantDirID,
PlantDirID
FROM @Plant p
LEFT JOIN (SELECT PlantID,
MAX(CASE WHEN Assistant = 1 THEN PlantDirectorID END) AS PlantAssistantDirID,
MAX(CASE WHEN Assistant = 0 THEN PlantDirectorID END) AS PlantDirID
@PlantDirector
GROUP BY PlantID)pd
ON pd.PlantID = p.PlantID
Please Mark This As Answer if it helps to solve the issue Visakh ---------------------------- http://visakhm.blogspot.com/ https://www.facebook.com/VmBlogs
You're missing a FROM
insert into @PlantNew
SELECT p.PlantID,
p.PlantName,
CASE WHEN pd.PlantID IS NULL THEN 0 ELSE 1 END,
PlantAssistantDirID,
PlantDirID
FROM @Plant p
LEFT JOIN (SELECT PlantID,
MAX(CASE WHEN Assistant = 1 THEN PlantDirectorID END) AS PlantAssistantDirID,
MAX(CASE WHEN Assistant = 0 THEN PlantDirectorID END) AS PlantDirID
from @PlantDirector
GROUP BY PlantID)pd
ON pd.PlantID = p.PlantID

Acquiring two signals and saving at a Table

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