SiS_SetRegAND(SISIOADDRESS Port,USHORT Index,USHORT DataAND)
SiS_SetRegAND(SISIOADDRESS Port, unsigned short Index, unsigned short DataAND)
SiS_SetRegAND(SISIOADDRESS Port,USHORT Index,USHORT DataAND){  USHORT temp;  temp = SiS_GetReg(Port,Index);  temp &= DataAND;  SiS_SetReg(Port,Index,temp);}