Need Help for Using Gdb!

Hi,everyone.
I want to use gdb to debug execuable on my board.
The host and target systems are connected via a serial port ,
and then i type command “pdebug /dev/ser1,115200 &” to start debug agent (pdebug). When i run pidin from the console,I can assert the pdebug process is running well.
Then from the host ,i start gdb to connect to my target. and then type “target qnx com1” and “info pid” from the , every is well.
But when i want to run a process as to type ‘run ls’, i have no message received, and after several second the TimedOut appeared.
And there is another thing to say.If i connect to the target using TCP/IP,every thing is also very well.

Is there anyone can tell me what is wrong ? 

Thanks.

If you are just indicating run ls, then gdb is going to assume that what you started it up as
will contain a binary image to map to for debugging.

There were also some bugs with our early gdb releases that were confused if you launched
gdb with one set of arguments but then did a run.

What version of Momentics are you using (try the latest 6.3.2 download from foundry27.com)
and can you show the command outputs for how you are launching gdb.

Or try the Bit Torrent:
openqnx.com/downloads/QNX-6. … so.torrent