Can't commuicate with serial port while power is on

[JBadon]

I need some help with communcating with the serial port.  I tried using the Hyperterminal and at first it said that my port was busy.  I didn't think it was, but then I noticed that the power on the device that hooks up to it was turned on.  When I turned the power off, I was able to connect.  I can't run my program with the power off, so now what do I do?  I need some help configuring the VISA.  Can someone please help me?

[AnalogKid2DigitalMan]

Have you tried a full power down of the PC?

If your code or another application did not properly close the port, it may be unavailable to all other programs. Be sure to include the VISA Close in your own LV code before exiting the vi. What is the make and model of the instrument you are connecting to and do you have the proper cable?

[JBadon]

Before using Labview, I used a program called TestPoint.  The program that was created using the other software controlled my setup, but it couldn't multi-task like Labview and it lacked other key features.  With that being said, I'm sure I have the correct cables.  I'm trying to control a motor along with some other functions. Here is what I'm dealing with:

http://www.a-m-c.com/download/datasheet/DR100EE30A40NAC.pdf  

This device requires power in order to function, but when I turn it on I can no longer communicate with the serial port because it's busy with the driver.  I need a lot of advice.  Help!

[AnalogKid2DigitalMan]

According to AMC's documents, you need a straight through cable for this drive (not a null modem cable where pins 2 and 3 get swapped). Have you attempted communications with AMC's own program just to verify drive's port is not damaged? See:

http://www.a-m-c.com/content/support/digital/100series.html#rs232

Verify this first, If OK, then I suggest you power everything down and back up and try communications with Hyperterminal as the next step. Let us know how it goes.

[JBadon]

I looked at the RS232 cable and it has been modified to be a straight thru cable, so how will this affect the way it communicates?  Is there something different that I have to do in Labview because of this?

[AnalogKid2DigitalMan]

The straight through cable is what you need, regardless of program used to communicate. Should not need to do anything special in LV. Any luck with AMC's communication program?

[JBadon]

I already had the AMC program installed on the computer.  I ran it and it worked fine.  I just don't know what I'm doing wrong with trying to communicate.  It's communicating correctly when I use the old program, but not this one.  I know something isn't configured right, but I can't figure out what it is.  What do you think it is?

[daijoubu]

When you tested with HyperTerminal, was it right after rebooting the PC or did you use AMCs program first?  Did you try cycling the power to the PC and then going straight to HyperTerminal as AnalogKid2DigitalMan suggested?

[JBadon]

I restarted the computer and then tried the Hyperterminal, but I still get the same problem with the power.  When the power for the system is on, it will not communicate throught the hyperterminal, but it can through the program I created in TestPoint.  I then tried turning noff the computer and trying AMC software and then the Hyperterminal and still the same problem.  The AMC software simply checks and rests the controller.  Everything appears to be fine.  I created a small VI to read the bits off the controller and I got an error: 1073807339-Time expired before operation completed.  This is probably because I don't have something set up correctly or that it simply cannot communicate.  I don't understand why it can communicate using some cheap program and not LV.  Any suggestions?

[AnalogKid2DigitalMan]

JBadon:

I wish I had something concrete for you to pursue. All I can assume is that you have used ALL the SAME settings from your Testpoint program (COM port #, baud, parity, stop and data bits, handshaking, TERMINATION CHARACTER, etc) for your Hyperterminal setup and LV code. I capitalized termination character because Hyperterminal typically automatically adds a linefeed and/or carriage return to the end of the transmitted string. Please double check all the settings. Other than that, I am clueless right now