How to monitor RS-232 PC port1 (i.e. COM1)? [closed]

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I have a Microcontroller Development board that is connected to my PC via RS-232 DB-9 serial COM port (whatever one you want to call it).

The Micro has built in monitor code that uses functions like printf() and putchar() to produce console output on the PC side monitoring application.

I want to use this output functionality to transmit data to my own PC application but I cannot disable the monitoring program.

Is there a way I can "eavesdrop" on the COM port to listen for my start byte and data that I want to send? I don't need to send to the micro, just receive.

If possible, I'd like to do it in java for the sake of the rest of the application, but I will take .NET answers as well.

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Yes, there are a few ways of doing this in software. I use this free software: http://www.serial-port-monitor.com

Franson also makes serial port splitter software, which opens up virtual COM ports on your PC, which your software connects to and the other software connects to. This is not free.

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I just know this way using hardware RS232-Spy.

http://www.lammertbies.nl/comm/cable/RS-232-spy-monitor.html

Good look!

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I think you might be interested in com0com.

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Use a voltage compatible USB-to-serial dongle which will act as a new COM port. Use wire-wrap wires to splice into the RX, TX, and GND connections. Use TeraTerm on the PC to open and view the new COM port. Both RX and TX will work; although collisions when both are transmitting will likely yield garbage.

Note that by doing this, your PC's ground will be connected to the hardware board's ground, through the USB ground on the USB-to-serial dongle. This is usually OK for simple development tasks.