Send data via RS232 with a transparent device

[CarlosSp]

Hi, I would want to send data continously with a radiomodem that is connected via RS232 with an adapter RS232/USB in a laptop. Using the VISA commands there's no way I can do it cause in the pin of resource name it dpesn't recognice any device, although I connect the radiomodem to the laptot. How can I send data via RS232 without specifiying the divice I'm using?

Thanks

[RavensFan]

I'm sorry, but your message is a little confusing.

What is a "pin" of resource name?

What do you mean by a transparent device?

RS-232/USB adapters generally create a Virtual Com port with their driver that will show up in Windows System Manager, and thus MAX such as a Com6 (usually a number higher than any real serial ports you have, modems, and some lof the extra wireless/bluetooth stuff a laptop may have).  You would be able to use the resource name.

[CarlosSp]

Well, the "pin" resource name is the left upper connection that you can do in the VISA W or R in wich you have to place the device you are going to use via that port. In my case, I have the virtual COM port as you say, but I connect a radiomodem and it is like a transparent device. I mean that the PC doens't recognice any device, I only have to send data via RS232 port and the raiomodem does the rest of the transmission. The problem is that I do'nt know how to do that with Labview because I have used VISA but in the "resource name" connection I placed the name of the device I used.

Mensaje editado por CarlosSp

[RavensFan]

"Pin" isn't the usual terminology.  It would usually be connector pane.

What is the device you are trying to communicate with?  Do you have another radio modem on the other end that takes it from wireless back to an RS-232 connection on this device?

In your VISA resource name, you would put the Com6 or whatever is the virtual serial port number assigned to your USB adapter.  LabVIEW and MAX have no idea about the name of the device you are connecting to.  They just know that ComX exists.

[CarlosSp]

Yes, I have another radiomodem that is connected to a PC104 that takes the data and cuts the string to send orders to another drivers to move some motors. The fact is that I don't have any option in the "Resource Name" pane, only I can refresh. You say that if I write the name of the port f.e.: COM1, the data will be sent via that port???

[RavensFan]

Correct.  Select whatever com port is shown in that VISA name control based on how your USB device shows up in Windows.  If the USB adapter shows up as Com1, then select Com1.  Windows will then know to send your VISA writes and Reads in and out through the USB adapter.  It will handle the conversion to RS-232.  The radio modem will handle the conversion from RS-232 to the wireless radio.  The other wireless radio will convet it back again to RS-232 plugged into your PC104.

[CarlosSp]

Ok, that would be great if I had the option to select the COM port in that VISA name control (guess you refer to the resource name), but I have no option to choose, only "Refresh" 🙂 that's my problem.

[RavensFan]

Does the Com port show up in Windows system manager?

Do you see it in MAX?  Is the USB adapter currently plugged in?

[CarlosSp]

Yes, it is correctly plugged in, drivers are installed and Windows recognizes it perfectly. I can configure the port as an RS232 port (bauds, parity...) . Sorry but what's MAX??

[RavensFan]

MAX is Measurement and Automation Explorer.  It gets installed when you install the device drivers such as NI-VISA.

Have you installed the device driver CD or DVD after your latest installation of LabVIEW?