RTL_TCP Commands

Sending commands to RTL_TCP What format do the commands need to be in order to change the frequency of RTL_TCP. I have tried the following and the frequency will change but no to the frequency that is expected for example: This code : char SET_FREQUENCY[] ={0x01}; string Freq = string(SET_FREQUENCY,1)+"500000000"; answer = send(sConnect,Freq.c_str(),11,0); Changes the freq to this: client accepted! set freq 892350512 ll+, now 1 ll+, now 2 Any help would be greatly appreciated as i have been stuck on this for days. Thanks