Sending string using a serial com when clicking on a button

[scls19fr]

Hello,

I would like to send a string using a serial com when I click on a button (4 buttons are possible)

I'm using polling on buttons and testing if string is empty.

(see main.vi and buttons_pressed.vi)

When there is so many button polling is not a good thing so I'd like to change my code to use events structure.

So first I made a minimal vi called ecu_keys.vi

I think that I shouldn't set timeout value to 0 because I have a very high CPU usage !

Moreover I don't see the string changing when I click on one of the buttons.

I also wonder how I should modify my VI to fit with "VISA Write"

Best regards

VI are available here

http://svn.berlios.de/viewcvs/openphysic/l...bo-wrenturbines

or svn checkout svn://svn.berlios.de/openphysic/labview/turbo-wrenturbines

see trunk directory

I also join the files in this post

Download File:post-11213-1207857774.vi

Download File:post-11213-1207857765.vi

Download File:post-11213-1207857753.vi

Download File:post-11213-1207857738.vi

Download File:post-11213-1207857711.vi

Download File:post-11213-1207857703.vi

Download File:post-11213-1207857694.vi

Download File:post-11213-1207857685.vi

Download File:post-11213-1207857677.vi

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LAVAG is great !

LAVAG people are great !

[MikaelH]

Hi

I downloaded the trunk from SVN, and that worked great :-)

I've attached a VI with some things to consider.

Download File:post-941-1207866659.vi

Cheers,

Mikael

[scls19fr]

Thanks for your reply.

I see that you put the VISA Write inside the event struct...

Is it really a good idea ? since I hear that the code inside an event struct must

be minimal... (because it can freeze the GUI)

About the data reiceveid... there is no terminaison characters.

String is send by the ECU byte after byte... not as a string

so I need to make a little hack (reading only one byte) in order to synchronize data received

with 252 253 (first two bytes)

Here is the protocol http://www.espiell.com/fadprot.pdf for received data (coming from the ECU)

And the protocol for sending key pressed

2 first bytes (222 et 223), adress (112 for commands), value, checksum (adress+value)

Menu up 222,223,112,67,179

Menu down 222,223,112,68,180

Data up 222,223,112,65,177

Data down 222,223,112,66,178

Orko (an other LAVA member) said me to use queues

CITATION

That is when queues are useful. Enqueuing an item in an event strucure is very fast, and another loop can dequeue the item and take all the time it needs to complete the task (producer/consumer).

Did you ever use them ?

Best regards

Sebastien