byte[] miBuffer
= new byte[9]; //enviamos trama: @02DO03 miBuffer[0] = 0x40; // @
miBuffer[1] = 0x30; // 0
miBuffer[2] = 0x32; // 2
miBuffer[3] = 0x44; // D
miBuffer[4] = 0x4F; // O
miBuffer[5] = 0x30; // 0
miBuffer[6] = 0x33; // 0
miBuffer[7] = 0x0A; //chr 10
miBuffer[8] = 0x0D; //chr 13
this.serialPort1.Write(miBuffer, 0, miBuffer.Length);