ERROR->1073807339 occured at VISA read in Labview->Serial.vi

[roiht]

Hiiii
I'm using LabView7.0 profesional edition and a begineer in LabView.
I'm using PIC18F4520 microcontroller to communicate with the serial
port RS232 and transmit the data whatevr it is receiveing immediately
using asynchronous EUSART , but everytime i run Serial.vi provided in
examples i get the error - 1073807339 occured at VISA read in LabView.
I have preformed the loopback test in Labview and it is doing well and
other configurations of COMM1 port are correct to my knowledge..
I'm attatching the code written in MPLAB IDE for PIC and the serial.vi
i'm using present in the installaiton examplesfor the same.
Please help me in debugging this problem as i'm out of ideas now
hoping for a helpful hand asap...........
thanks
rohit


basicserial.c:
http://forums.ni.com/attachments/ni/170/184195/1/basicserial.c

[roiht]

I tried using my code in hyper terminal it is able to send and receive
data but in labview it is continuously creating such problems and
giving the same error i have checked the baud rate parity bits and stop
bits etc.
but nothig seems to wrktillnow
please help as im getting stuck
thanks

[JoeLabView]

Here is the definition of the error code:
"VISA:  (Hex 0xBFFF0015) Timeout expired before operation completed."
How did you implement the serial read in Labview?  You mentionned that you are using the example.  I'm assuming it is the one that came with LV.  The first thought would be to simply extend the timeout duration...  however...
The code shows that REGisters are set for Tx & Rx.  However, I do not see how the data / info is sent to the serial buffer.   What value are you wiring to the Serial Read input (bytes available at serial port)?  and how do you determine the value?   One example with LV7.1 uses the Property Node to read the number of bytes available at the serial port.  If you are using something similar, what is the value for the no. of bytes at the port? 
There is an advanced example that forces to read a certain amount of data or timeout.  It also indicates how many bytes it actually read.  If it is not able to read the number of bytes requested, then it will generate a timeout error.  See images below:
JLV 
 
Basic Example
<img src="Loading Image...">
&nbsp;
Advanced Example:
<img src="Loading Image...">
Message Edited by JoeLabView on 05-11-2006 08:32 AM


serial example.JPG:
http://forums.ni.com/attachments/ni/170/184258/1/serial example.JPG


serial error.JPG:
http://forums.ni.com/attachments/ni/170/184258/2/serial error.JPG

[roiht]

Thanks a lot
&nbsp;for the support providid any way i figured out my problem and
have modified&nbsp; my vi i'm atttatcing it...which can be of help to
someone else............
thanks once again
rohit


Serial_general.vi:
http://forums.ni.com/attachments/ni/170/184298/1/Serial_general.vi