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Write among COM ports in the same PC without cables

How can I write to the memory address(es) of a serial COM port?  I would like to send data from one serial COM port to another in a manner similar to the that of the 'Simple Data Client' and 'Simple Data Server' vi examples.  This must sound strange since this is exactly what a null modem cable will do, externally.  I would like to eliminate the cable connection between COM ports that exsit in the same PC and communicate between them, internal to the PC, somehow. 
 
Currently, I am using a LabVIEW vi to read a serial message on COM1, translate it, send the trsanslation out on COM2, so that a separate windows program (no .DLLs to interface with LabVIEW) can read the message on COM 3.  COM 2 and COM 3 are connected by a null-modem cable.  This requires three COM ports, and two serial cables.  I realize that I can use a physical loop-back jumper on COM2, for instance, where I send and read the translated message on COM2, but I still wonder if there is a method for doing this in memory, or something. Is there a way to accomplish the same objective with one cable (into COM1), no loop-back jumpers, and only two serial ports?  In summary, I want to read on COM 1, translate in LabVIEW, then write directly to another COM port, internally, without using a serial cable.  Can the 'IN PORT' or 'OUT PORT' vi's apply here?  Are these tools only for parallel ports?
 
Hope this is not too confusing....  It seems like I am always trying to do something with LabVIEW that was not meant to be done....
 
Thanks.
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Perhaps this will help. You might be able to find a free version somewhere on the web.

http://www.topshareware.com/Virtual-Serial-Ports-Driver-XP-download-3571.htm

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Thank you.  If I pay the price they ask, this looks like it will create and share virtual COM ports - exactly what I need.  However, I would really like to find a way to do this in LabVIEW, such that I do not have to make my application dependent on another piece of third party software.  The 'Simple Data Client.vi' and 'Simple Data Server.vi', included in the shipset examples, seem to do this for TCP/ IP ports.  I wonder why the COM ports cannot be addressed at the memory level, in a similar manner???
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