Serial Commuinications

[cmm72352]

I'm trying to figure out how to communicate with a California Instruments Model 801PR Power Generator using the Com1: port.   I've tried example serial programs in Labview and get the following error:

Error -1073807346 occurred at VISA Open in Serial Communication.vi.

Possible reasons:

VISA:  (Hex 0xBFFF000E) The given session or object reference is invalid.

When I try running an "initialization VI" that was provided with the 801PR (in the CICRP50 vi lib) I get the following message:

Error -1074135040 occurred at CIC_RP50 Initialize.vi.

Possible reasons:

IVI:  (Hex 0xBFFA0000) Cannot load IVI engine.

Does anyone know what this means and is anyone able to offer advice on how to communicate via the serial port. I'm using Labview 6.1 and this is my first project.

[tbob]

Labview cannot find your serial port.  What are you using as the VISA Resource Name on the input of the VISA Configure Serial Port function?  It should be ASRL1 or COM1 for serial port 1.  The best way to do this is to go to the block diagram and right click on the VISA Resource Name input at the top left corner of the configure vi.  Then select Create - Control.  The control will be placed on the front panel.  Click on the drop down list and you will see the ports that your computer recognizes.  Choose ASRLx or COMx (x=1,2,etc).  This should clear the error.  If you have no items listed in the drop down box, your serial ports are not set up.  You need to clear this up with the OS first.

[cmm72352]

The resouce name is ASRL1::INSTR   I just tried running it again and the error is:

Error -1073807346 occurred at VISA Open in Serial Communication.vi.

Possible reasons:

VISA:  (Hex 0xBFFF000E) The given session or object reference is invalid.

[tbob]

Open MAX and see if the serial port is listed there under Devices and Interfaces - Ports.  It should be listed as COM1 or ASRL1.  Click on COM1 and click the general tab.  There is a box in there that should say the device is working properly.  If not, then your com port is not installed properly.  If it is there, then perhaps Labview wasn't installed properly.  Also, make sure no other device has the com port open, like a modem or something else.  If you have a modem, it may be using COM1.  You would have to reconfigure it for COM2, or use COM2 in your Labview program.

[cmm72352]

When I open MAX all that shows is:

My System

       Data Neighborhood

                    Traditional NI-DAQ Vitual Channels

       Devices and Interfaces

                     Traditional NI-DAQ Devices

                                 PCI-6014 (Device 1)

       Scales

       Software

       IVI Drivers

Remote Systems

[tbob]

This tells me that you don't have any serial ports on your system.  Without seeng it or knowing anything more, there is little I can do.  Contact the source that you bought your computer from.  Most computers come with a serial port built onto the motherboard.  You need to check with the vendor to see if your system has a serial port installed.  If so, you may have to go into the BIOS to set it up.  Again your vendor should be able to help you with this.

[cmm72352]

It has a serial port:

    I/O Range      03F8-03FF

    IRQ                04

[Dynamik]

Hi cmm,

      Before you can use the serial-port in LabVIEW, MAX has to "see" it.  Normally,  in MAX, it appears per pic. (attached)

If you don't see the "COM" port in MAX, try VIEW\Refresh - (MAX will look for "new" devices.)

If it _still_ doesn't show-up, you may have some hardware conflict.  Can you use the port under Windows' Hyperterminal?  (use a loop-back connector to confirm operation.)

Cheers

[cmm72352]

For some reason MAX isn't recognizing any of my ports. I've tried accessing the COM1 port under Windows Hyperterminal and it works. I also tried reloading MAX and that didn't help either.

[tbob]

Are you using XP?  I've heard of people having serial port problems with XP.  You may have to get some patch from MS to make the serial port accessible to other programs.  Also, reboot and go to the BIOS setup screen before the OS comes up.  Look at the com port settings there to see if anything looks funny, like the port being set to disable or something.