FezBootloaderController.cs

using System;
using System.IO;
using System.IO.Ports;
using System.Management;

namespace Prototype.Fez.BootloaderUtil
{
    internal class FezBootloaderController
    {
        private SerialPort _fezPort;

        internal void Open()
        {
            _fezPort = OpenFezBootloaderSerialPort();
            _fezPort.Open();
            _fezPort.NewLine = "\r\n";
        }

        // http://www.codeproject.com/Messages/3692563/Get-correct-driver-name-from-Device-management-ass.aspx
        // http://geekswithblogs.net/PsychoCoder/archive/2008/01/25/using_wmi_in_csharp.aspx

        private static SerialPort OpenFezBootloaderSerialPort()
        {
            var searcher =
                new ManagementObjectSearcher(
                    "select DeviceID,MaxBaudRate from Win32_SerialPort where Description = \"GHI Boot Loader Interface\"");
            foreach (ManagementBaseObject obj in searcher.Get())
            {
                return new SerialPort((string) obj["DeviceID"], (int) (uint) obj["MaxBaudRate"]);
            }
            throw new FezBootloaderException("Unable to find FEZ device. Is it in bootloader mode?");
        }

        internal string GetLoaderVersion()
        {
            SendCommand(FezCommand.GetLoaderVersion);
            string response = _fezPort.ReadLine();
            _fezPort.ReadLine(); // Eat trailing BL\r\n
            return response;
        }

        private void SendCommand(FezCommand fezCommand)
        {
            _fezPort.Write(new[] {(byte) fezCommand}, 0, 1);
        }

        internal void LoadFirmware(string filename)
        {
            // Load the file into a memory block

            byte[] data = ReadFileIntoByteArray(filename);

            // Set up an XMODEM object

            var xmodem = new XModem.XModem(_fezPort);
            int bytesSent = 0;
            xmodem.PacketSent += (sender, args) =>
                                     {
                                         bytesSent += 1024;
                                         Console.Write("{0}% sent\r", Math.Min(bytesSent, data.Length)*100/data.Length);
                                     };

            // Tell the FEZ to get ready for some firmware

            SendCommand(FezCommand.LoadFirmware);
            _fezPort.ReadLine(); // Eat "Start File Transfer" chit chat

            // Transfer the block

            int result = xmodem.XmodemTransmit(data, data.Length, true);

            // Throw an exception if anything freaked

            if (result < data.Length)
            {
                throw new FezBootloaderException("Failed to transmit file " + result);
            }

            Console.WriteLine();

            // There is a bunch more yak on the serial port, and the device
            // has restarted in normal operation. You know, just FYI.
            //while (true)
            //{
            //    var line = fezPort.ReadLine();
            //    System.Console.WriteLine(line);
            //}

            Close();
        }

        private void Close()
        {
            try
            {
                _fezPort.Close();
            }
            catch (IOException)
            {
                // Nothing to see here. Move along.
                // When the FEZ reboots itself after a file upload, the serial
                // port is in a sad state. So be polite, do your best to close
                // it, and when he freaks out with:
                //
                // IOException: A device attached to the system is not functioning.
                //
                // Say "I never did mind the little things."
            }
            _fezPort = null;
        }

        private static byte[] ReadFileIntoByteArray(string filename)
        {
            MemoryStream outputStream;

            using (var inputStream = new FileStream(filename, FileMode.Open, FileAccess.Read))
            {
                outputStream = new MemoryStream((int) inputStream.Length);
                inputStream.CopyTo(outputStream);
            }

            return outputStream.ToArray();
        }

        #region Nested type: FezCommand

        private enum FezCommand : byte
        {
            None = 0,
            GetLoaderVersion = (Byte) 'V',
            LoadFirmware = (Byte) 'X',
        }

        #endregion
    }
}