LabVIEW

cancel
Showing results for 
Search instead for 
Did you mean: 

Serial read/write labview issue - trouble with lead/pin outs etc

I'm having trouble with serial communications with Labview.

 

Using the serial read/write example (Labview 2011) the data sends to Hyperterminal fine but does not read. I checked my pin outs are 2&3 crossed and 5 straight through. Following this I went to see a technician at Uni and they gave me a lead where you can put your own links in the middle of the cable to ensure correct connection and this lead worked fine. We assumed my lead purchased from ebay was giving issues as the other pins where also connected. Today I am at work and have made my own cable up to match the one from Uni with only pins 2&3 crossed and 5 straight through, and I can still only send the data and not read. I can't understand it, I've opened up hyperterminal on both computers and I can send and read data from both terminals so I can only think its an issue with labview but I'm using the standard read/write example.

 

Any ideas appreciated.

0 Kudos
Message 1 of 5
(2,183 Views)

How about posting your VI or a simplified version of it?

 

Albert

 

0 Kudos
Message 2 of 5
(2,169 Views)

Hi, the VI is the basic read/write example in labview as attached.

 

0 Kudos
Message 3 of 5
(2,161 Views)

How are you writing to the COM port ?

Are you writing before you start the LabVIEW vi ?

 

The basic example you have shown, only writes then wait and the read. But you have to write something from the other site while the vi is in waiting.

0 Kudos
Message 4 of 5
(2,156 Views)

Hi 

 

At Uni I was using the labview front panel (on a desktop Pc) via serial cable to my laptop which was running hyperterminal. I wasnt typing anything in hyperterminal, I was basically running the example VI which was sending a string to hyperterminal then reading it back in the two boxs shown on the attached picture. Thinking back now after reading your reply I wasnt actually sending anything from hyperterminal to Labview but it was still reading the last string sent to hyperterminal, I read its a kind of loop back test??

0 Kudos
Message 5 of 5
(2,149 Views)