ComWrite in labwindows

Hi,

I am facing problem in writing hex data to com port using ComWrite.  How i will make sure that whatever data sent is written to my target properly because i am not seeing any changes in my target.

Whenever i am trying to read data from my target which is continously sending some response i can read through comRead successfully but write doesnt goes well. I cross verified the same message with other termnial where i can write hex data. but in CVI i cant. your feedbacks are much appreciated.

int no_of_bytes=0;

char comdata[100] = {0x28,0x00,0x02,0x00,0x01,0x00,0x01,0x00,0x00,0x00,0x29};

no_of_bytes = ComWrt (COM_PORT, comdata, strlen(comdata));

thanks.