about debug!!!!



I’ m trying to connect the fastrack M1306B with a device through RS232 interface

This device has one memory and when it receives from fastrack a particular command it sends the memory data to the fastrack.

In debug Mode I have used the ‘External Com’ feature of the Wavecom Terminal Emulator so that I have connected the M1306B to one COM port on my PC, then i have connected the device to another COM (to the ‘External Com’).
In debug mode I have opened the ‘External Com’ (‘Open on line’) .
These are the problems:
If the device sends the data, the fastrack receives this data but
if the fastrack sends the data, the device do not receives this data.
I cannot watch the data flow.

I have tried to make a " Y " connection:
I have connected the M1306B to one COM port on my PC,then I have connected the Rx of my PC to Rx of the device and the Tx of my PC to Tx of the device.
In Release mode i can watch the data flow but in debug mode when I connect the device to the " Y " connection, i cannot watch the data flow and the application is the blocked

Any idea???