PDA While Loop using Bluetooth results in interface lockup
The PDA Module ships with an example project that demonstrates client/server Bluetooth communication. I decided to try it out with my PC acting as the server and my PDA as the client. The demo basically transmits waveform data continuously via Bluetooth from server to client. Attached is the code for the client PDA and the heart of the code is a while loop which continuously accepts data via Bluetooth and outputs the data onto the display. For the most part, this is the stock example VI
that ships but I had to modify the interface with an event structure so
that I could use the PDA virtual keyboard to enter in the proper server
address.
The Bluetooth portion of the demo actually works great! When the data set is set to random, the PDA very quickly displays new random data on the LCD.
The problem occurs when I try to stop the VI. Both the disconnect and Exit booleans are unresponsive when I tap their respective buttons. My desired application will behave similarly to this demo which is why this is of concern to me. Is there a better way to implement a continuous Bluetooth polling system but still retain the functionality of my front panel?
System specifications:
PDA Module 8.0.1
iPAQ hx2790
Windows Mobile 5.0.
Attachments:
NI PDA Bluetooth demo.JPG 106 KB
Hi,
Just by looking at the snapshot it is hard to tell what's going wrong. Since the bluetooth part is working fine, I would suggest that you try to strip the bluetooth part from your VI and run the VI in highlight execution mode. This should shed some light on what happens when you click on Stop or Exit buttons. If you still need help after that, please post your stripped VI here and someone from the community will be sure to help you out.
Regards,
Ankita
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Solved!
Go to Solution.
Attachments:
1. Tick Count.vi 27 KB
tickcoun2.vi 27 KBDataflow!
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Question about while loop using Timer?
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zhljh
Sent via Deja.com http://www.deja.com/
Before you buy.In article <87q5t2$7kh$[email protected]>, wrote:
>I am trying to use a while loop to read data from oscilloscope through
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class (given below). If I start only one instance of
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3. Is it bcoz of the same problem as given in Bug ID :
4098442 ?.
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"Because some native platforms only provide limited
ed buffer size for standard input and output streams,
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While loop using a timer object
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Attachments:
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How to put the break at the first place of execution While Loop
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Is it possible to have one while loop in another while loop
Is it?
Well, actually there are several possibilities:
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i have done the search on th basis of firstname and last name..here is the code
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please tel me what should be the code for while loop so that all the entries are fetched for each userHi princy,
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I do small program, I have many while loops and I want to connect wire (in my application) from each loop to AND gate then to another while loop, but how can I operate these wires to agree with the change of my application inside while loops.
If not clear :
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Help me if you have any idea please..........................Hi Rammo,
For the wire to carry the boolean condition from the while loop to an 'and' gate outside, the while loop must stop running
If you want the while loop to keep on running and still pass a boolean value to a destination outside the while loop, use any one of these: property nodes, global or local variables.
i am still not clear as to what you intend to say by this sentence
" I want the wire that comes out from the while loop will become TRUE if it in my application is TRUE inside while loop and the opposite is true. Because I want to connect the wire that comes out from while loop to AND gate than to another application"
plz tell me if the first part of this mail of mine answers your doubt or do you need more information?
regards
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ReadUTF() and exiting a server while loop
What I want to do is simple.. I want to be able to type "exit" into a client and send that message to the server... And exit the server while loop as a result.. Here is what I tried.
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Hello, I'm trying to figure out for a half a day how to unite two while loops in attached VI
The first while loop creates solid state machine that reacts on each button press and executes one of the case structure events. (this part works fine)
The second while loop, all the time generates random number, but it stops the generation during the time when one of the case structure events are executed. (this is the ticky part)
Any suggestions?
Solved!
Go to Solution.
Attachments:
SSM_v1.1.vi 15 KBIf you want your random number to stop while the user triggered events are executing you should be able to simplify your design quite a lot.
It can be done with one while loop using the timeout case.
Troy
CLDEach snowflake in an avalanche pleads not guilty. - Stanislaw J. Lec
I haven't failed, I've found 10,000 ways that don't work - Thomas Edison
Beware of the man who won't be bothered with details. - William Feather
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SubVi with feedback nodes used more than once inside a While Loop
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I have a subvi that does a set of operations and uses 3 feedback nodes. I am using this subvi inside a While Loop a total of 4 times. I've noticed that all instances used share the same result at each corresponding feedback node but I would like to have an individual result from each of them. Is there an easy way to go around this problem? I have come up with ways to avoid this: a) create a different vi for each time the subvi was used. b) use global variables instead of feedback nodes. Is there any easier way to go around this issue?
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Im using 9.0.
Solved!
Go to Solution.Attaching the code would be helpful. Anyway, I am not sure how multiple feedback nodes are supposed to operate so I will defer that to others to answer. As far as being able to use distinct values or instances if you are using a subVI you could mark it as reentrant. That way each call to it will behave as it it were a copy of the VI and it will have its own memory space. This should include the feedback node. You may be ending up with a single subVI and in reality a single feedback node. If you need to pass data between calls than simply wire the data through. You could also use an Action Engine to store and retrieve values. An AE is a MUCH better solution than a global variable.
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