USB to Serial Convertor ATEN uc 232a

I am using Aten UC232A Converter to communicate with my micro-controller device using 3 wire interface ie txd, rxd and ground. Though the converter gets detected and driver loaded in my suse11.2. The operation does not work. following are the logs.

any help?
yast

drivers/usb/serial/usb-serial.c: USB Serial support registered for pl2303
pl2303 4-2:1.0: pl2303 converter detected
usb 4-2: pl2303 converter now attached to ttyUSB0
usbcore: registered new interface driver pl2303
drivers/usb/serial/pl2303.c: Prolific PL2303 USB to serial adaptor driver
pl2303 ttyUSB0: pl2303 converter now disconnected from ttyUSB0
pl2303 4-2:1.0: device disconnected
pl2303 4-1:1.0: pl2303 converter detected
usb 4-1: pl2303 converter now attached to ttyUSB0

stty :

speed 9600 baud; rows 0; columns 0; line = 0;
intr = ^C; quit = ^; erase = ^?; kill = ^U; eof = ^D; eol = <undef>;
eol2 = <undef>; swtch = <undef>; start = ^Q; stop = ^S; susp = ^Z; rprnt = ^R;
werase = ^W; lnext = ^V; flush = ^O; min = 1; time = 0;
-parenb -parodd cs8 hupcl -cstopb cread clocal -crtscts
-ignbrk -brkint -ignpar -parmrk -inpck -istrip -inlcr -igncr icrnl ixon -ixoff
-iuclc -ixany -imaxbel -iutf8
opost -olcuc -ocrnl onlcr -onocr -onlret -ofill -ofdel nl0 cr0 tab0 bs0 vt0 ff0
-isig icanon iexten echo echoe echok -echonl -noflsh -xcase -tostop -echoprt
echoctl echoke

Make sure that the handshake lines CTS/RTS, DTD/DCD are looped back properly to let the serial interface know that it’s ok to transmit and receive data. A search should be able to find you the required loopbacks.

Hi
They are actually connected. I doubt whether being an attachment to usb does it need registration through a vendor product Id like stuff.(the m/c).