Serial Communication POLL issue

I have a question about serial polling using MATLAB. I have a C# Code (below) which works fine. I am trying to create a corresponding code in MATLAB to do the same task. What I have created doesn't seem to work. What am I doing wrong?

C# Code:

using System;
using System.Collections.Generic;
using System.Text;
using System.IO.Ports;
using System.Windows.Forms;
using System.Data;

namespace HypobaricChamberMonitor
{
    abstract class Vaisala
    {
        public abstract string GetConditions(string address);
        public abstract bool PortOpen();
        public abstract void CloseSP();

      }

      class PRT : Vaisala
      {
          int baudrate = 4800;
          int datawidth = 7;
          StopBits sb = StopBits.One;
          Parity pty = Parity.Even;
          string newline = "\r";
          int timeout = 1500;
          SerialPort sp;
          string conditions;
          private bool portOpen = false;

          //string address;

          public PRT(string comport, string address)
          {
              sp = new SerialPort(comport, baudrate, pty, datawidth, sb);
              sp.ReadTimeout = timeout;
              //sp.DtrEnable = true;
              //sp.RtsEnable = true;
              sp.NewLine = newline;

              try
              {
                  sp.Open();
                  portOpen = true;
              }
              catch { portOpen = false; MessageBox.Show("Serial Port failed to open.", "Warning", MessageBoxButtons.OK); };
              try
              {
                  sp.WriteLine("SMODE POLL");
                  sp.WriteLine("UNIT P MMHG");
                  conditions = sp.ReadLine();
                  sp.WriteLine("OPEN " + address);
                  sp.WriteLine("SEND " + address);
                  conditions = sp.ReadLine();
                  if (!conditions.Contains("P"))
                      conditions = sp.ReadLine();
              }
              catch { conditions = "P =  000.0 mmHg T= 00.0 'C RH= 00.0 %RH"; }
          }

          public override string GetConditions(string address)
          {
              string conditions;
              sp.WriteLine("SEND " + address);
              conditions = sp.ReadLine();
              if (!conditions.Contains("P"))
                  try
                  {
                      conditions = sp.ReadLine();
                  }
                  catch { conditions = "P =  000.0 mmHg T= 00.0 'C RH= 00.0 %RH"; };
              return conditions;
          }

          public override bool PortOpen()
          {
              return portOpen; 
          }

          public override void CloseSP()
          {
              if (sp.IsOpen)
                  sp.Close();

          }
      }
  }

MATLAB Code:

s = serial('COM9');
set (s, 'BaudRate', 4800, 'DataBits', 7, 'Parity', 'Even', 'StopBits', 1);
fopen(s);
fprintf(s, 'SMODE POLL');
fprintf(s, 'UNIT P MMHG');
pause(2);
fprintf(s,'OPEN');
fprintf(s,'SEND');
pause(1);
Data = fscanf(s)
fclose(s);
clear s

In the MATLAB Code, I am just trying to Open COM Port, Get Data, and Close the Port. Thank you.