12-20-2010 08:20 PM
Hi everyone, I am having a hard time trying to solve the this particular problem ( probably because I am a newb to lanbview ). Anyway , I am able to save the acquired waveforms by using the 'Write to text file' icon. I did manually modify the block diagram of the 'Write to text file' icon and create the correct number of connector so as to make my program work. But now I have no idea on how to modify the block diagram of the 'Read from text file' block diagram to make my program 'open' my saved waveforms. Or i do not have to modify anything from the block diagram of the 'Read from text file'? Can anyone teach/help me connect up? Do i need the build array on the "open" page?
Here are some screenshots on part of my program
let me know if you guys would need more information / screenshots thank you!
12-20-2010 08:43 PM - edited 12-20-2010 08:45 PM
What is your LabVIEW version. In all recent version "write to text file" in not something you can modify. Your modification was very misguided and shows very poor understanding of LabVIEW and dataflow. (e.g. Why is the orange array terminal inside the loop? Why is array to spreadsheet string inside the loop? Why do you loop multiple times if you are always writing the same data? Why is there a 500ms delay? That makes no sense even though you added a diagram comment)
You should never modify stock VI. If the connectors don't match, you are using the wrong tools! For example, "write to spreadsheet file" is probably what you want.
Please attach your VI instead of images. We cannot debug images.
12-20-2010 08:45 PM
Why are you making it so difficult for yourself? Simply write using the Write to Spreadsheet File and read with the Read From Spreadsheet File.
Don't really know what VIs you are modifying. Write to Text File and Read From Text File are functions you cannot modify. Are you using an old version of LabVIEW?
12-20-2010 08:56 PM
I'm really a noob at this, I kept whats there is because it worked :x Only recently started learning how to use labview. sorry people. Will attach my vi now. :\
12-20-2010 09:09 PM - edited 12-20-2010 09:14 PM
Well, better look in the file IO palette next time. It's all there!
Here's a quick draft. I also left some other random diagram comments.
(You did not attach any subVIs so I cannot test. There could be bugs)
NOTE: you don't need any value properties. There is an execute VI option to "clear indicators when called".
12-20-2010 09:23 PM
Ohmy, thanks altenbach. oh yeah i forgot about those sub VIs. will upload them now. Was rather demoralized after reading the comments and really struck me on how weak i'm at on labview really hope to get this done. But of course i have to study through and see how it works. Actually i am going to replace those 'signal generators sub vi' with ThoughtTechonology's sample code so i can obtain data waveforms real-time using Electrocardiography (ECG) ,Electromyography (EMG ) and Electroencephalography (EEG) hopefully i can find out how to connect the sample code.
( ps . cant connect it now unless my program is working otherwise labview will crash )
( p.s.s the encoder of my biofeedback trainer already acts as an DAQ so i wont need to place an DAQ assistant in my block diagram i suppose )
The sample code of ThoughtTechnology is named as attachment.ashx.vi. too bad i cant use it and present it as my project