I also read it's Obsolete.

What can be the alternative handshaking options i
could not find any other way.And also my device
firmware should understand it.

How can i put waits for slow devices.

I am now getting the desired ouput by changing the
PARITY of the serial  port config to NONE.In windows  it
was working with EVEN PARITY.

I have just put loops to wait for the device to
respond.Suggest any other way...