The "VISA Configure Serial Port" VI will only run at 9600 Baud

Question

I have written a Serial Port monitor "RS232 RW.vi"  that works for the most part. The problem is that it will not respond to alternate port configuration settings.... For instance: the default RS232 Serial port configuration is:
(COM1,9600 baud,8 data bits,1 Stop bit, None no parity)
As a test, I am using a Null Modem Cable to connect From my LabView Com1 port to another PC running RealTerm Serial Port Monitor.. Using my newly designed "RS232 RW.vi"  With port settings of (COM1,9600 baud,8 data bits,1 Stop bit, None no parity),  I can send and receive data back and forth all day long no problems....
However, if I configure the "RS232 RW.vi"  port to any other configuration, such as (COM1,2400 baud ,7 data bits,1 stop bit, Odd parity).. It will not take the expected chances and continues to operate @ 9600 baud etc.
I then changed the "RS232 RW.vi"  default settings to (2400,7,1,Odd)
it still refuses to deviate from (COM1, 9600,8,1,None...)
I also went into the Win XP  Device Manager on the LabView system and manually configured Com1 to 2400,7,1,Odd  
and still,.... the "RS232 RW.vi"  will only operate @ 9600,8,1,None
Can anyone else test drive my VI and see if they have the same problem of not being able to see new changes in the Port configuration settings ..other than (COM1, 9600,8,1,None...).... ?
FYI.. Unfortunately my LabView is running on Version 6.0 so you may need to up-convert the attached vi
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Attachments:
RS232 RW.vi ‏102 KB

Answer 1

Instead of just appreciating the comments, you need to implement them.
Having the VISA close inside the loop is definitely the problem.  And Crossrulz is 100% correct about the problem being that the serial port gets reset to the default baud rate after closing the port.  Here is the proof.
Note that while you may have set the port settings manually in device manager, those settings are revised by the VISA driver.  If you look in Measurement and Automation Explorer under Devices and Interfaces >> Serial and Parallel, you'll see the default settings that the VISA driver uses.  If you change the setting there, your program will work the way you want.  But that is not the correct fix.  The correct fix is to get the VISA close out of the while loop.
The port settings are established in this order.
1.  By the Windows device drivers.
2.  By the VISA driver as established in MAX.  Since you are useing VISA, these settings will automatically override #1.
3.  By the port settings you set programmatically in your LabVIEW program.
Attachments:
Example_VI.png ‏18 KB