This might help you I am trying to write data to serialport and then wait for the acknowledgement. After ack is received, I write the next set of data. Please suggest a way of doing this. I tried the below code but before receiving the ack, the writing fires and completes execution. , Somehow this has worked out,
byte data = "Your message to be sent on serial port";
serialPort.Write(data, 0, data.Length);
byte buffer = new byte;
int vintctr = 0;
while (vintctr < 16)
vintctr += serialPort.Read(buffer, 0, 16);
Debug this and you you can get the reply from the port.