Using Virtual Serial Port Manager
Setting a local bridge to connect the 2 virtual serial ports allows a Max patch to communicate with a radio on a real serial port and pass through the data to a virtual serial port that can be used by another program, such as a logger. The patch looks like this:
Its looks like a feedback loop but its not. In this case the bridge is: com1 <-> com2. Com1 is port a in the above patch. Data sent to com1 can be read from com2 and vice versa.