I think you can just do the following:
1) Talk to the instruments that have the common setup
2) Perform an Execute Close on the serial port using Direct I/O
3) Talk to the instruments with the other setup
4) Perform another execute close.
I have done this when I used a common serial port with two programs and needed to release the port.
From: Shawn Fessenden [mailto:firstname.lastname@example.org]
Sent: Tuesday, March 28, 2006 2:11 PM
Subject: RE: [vrf] Communications changes
Define two serial instruments, one with no parity and one with even parity. Try communicating with one. Feed an error pin to a close transaction and then try the other. You can do the same thing by varying the parameters dynamically, but the port has to be closed when you change parameters.
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