private byte[] ConstructPacket(int deviceAddress, RWMode readOrWrite, CommandCategory category, string command, params byte[] data)
{
List <byte> packet = new List <byte>(14 + data.Length);
// 0
packet.Add((byte)Terminator.Start);
// 1-4
packet.AddRange(Address(deviceAddress));
// 5
packet.Add((byte)readOrWrite);
// 6
packet.Add((byte)category);
// 7-9
packet.AddRange(ToAsciiBytes(command, 3, 0x00));
// 10
packet.Add((byte)Terminator.Separator);
if (data.Length > 0)
{
packet.AddRange(data);
}
packet.Add((byte)Terminator.Separator);
packet.Add(CheckSum(packet));
packet.Add((byte)Terminator.End);
return(packet.ToArray());
}
private void ExceptionHandler(VisaException ve, RWMode rw)
{
if (rw == RWMode.Read)
{
Console.Write("LOST READ ");
}
else
{
Console.Write("LOST WRITE ");
}
Console.WriteLine("Last command: " + lastCmd);
Console.WriteLine("Visa Exception type " + ve.ErrorCode.ToString());
if ((ve.ErrorCode == VisaStatus.ErrorSystemError ||
ve.ErrorCode == VisaStatus.ErrorTimeout ||
ve.ErrorCode == VisaStatus.ErrorConnectionLost ||
ve.ErrorCode == VisaStatus.ErrorIO ||
ve.ErrorCode == VisaStatus.ErrorNotControllerInChange) && rw == RWMode.Write)
{
// something major has happened to cause a Write to timeout
// If writes are timing out, we don't want to waste time trying to close the connection down cleanly,
// because that will probably timeout too. Instead, just set the instrument object to null.
// Close ( );
if (visaHandle != 0)
{
visaHandle = 0;
liveConnection = false;
// since we've lost the connection to the instrument, rethrow the exception with an explanation message
// and tell them we've lost the connection.
VisaException writeTimeoutException = new VisaException(VisaStatus.ErrorConnectionLost, "The connection to " + this.Address + " has been lost.", ve);
throw writeTimeoutException;
}
}
else if (ve.ErrorCode == VisaStatus.ErrorConnectionLost || ve.ErrorCode == VisaStatus.ErrorIO || ve.ErrorCode == VisaStatus.ErrorSystemError)
{
if (visaHandle != 0)
{
// this should prevent every thread from getting hung with Visa Timeouts
Close();
visaHandle = 0;
liveConnection = false;
throw ve;
}
}
// else if ( ve.ErrorCode = VisaStatus.ErrorTimeout && rw == RWMode.Read )
// timed out on a read - may be bacause the query data wasn't available
// or that something is up with the visa connection.
// Assume its not a catastrophic event and try to continue on
if (!HandleVisaExceptions)
{
throw ve;
}
}
/// <summary>
/// Set the mode based on the string. If it's one of the RWMode values, returns true.
/// </summary>
public static bool SetMode(string value)
{
modeStr = value ?? string.Empty;
if (value != null)
{
bool success = Enum.TryParse(value, out RWMode res);
mode = success ? res : RWMode.None;
return(success);
}
mode = RWMode.None;
return(false);
}
public static byte ModeToByte(RWMode mode)
{
switch (mode)
{
case RWMode.READ:
return(0x0);
case RWMode.WRITE:
return(0x1);
default:
return(0x2);
}
}
public static string ModeToString(RWMode mode)
{
switch (mode)
{
case RWMode.READ:
return("READ");
case RWMode.WRITE:
return("READ");
default:
return("UNDEF");
}
}
internal override string RawCommand(string userinput)
{
string reply = string.Empty;
try
{
string[] parts = userinput.Split(new char[] { ';' }, 2);
RWMode mode = (RWMode)parts[0][0];
CommandCategory cat = (CommandCategory)parts[0][1];
string cmd = parts[0].Substring(2, 3);
reply = mode + " " + cat + "-" + cmd + Environment.NewLine;
byte[] data = new byte[0];
if (parts.Length == 2)
{
data = System.Text.Encoding.ASCII.GetBytes(parts[1]);
}
byte[] packet = ConstructPacket(_deviceAddress, mode, cat, cmd, data);
bool success;
byte[] response = BlockingSend(packet, out success, Vislink_HDR1000.ETX);
if (response != null)
{
int addr;
ResponseStatus status;
byte[] respData;
ParseResponse(response, out addr, out status, out respData);
reply += "Received Bytes: " + ByteArrayToString(response) + Environment.NewLine;
reply += " Addr = " + addr + " Status = " + status + " (" + (char)status + ") Data = \"" + ToAsciiChars(respData) + "\"" + Environment.NewLine;
}
else
{
reply += "<no response received>" + Environment.NewLine;
}
}
catch (Exception ex)
{
reply += Environment.NewLine + ex.ToString();
}
return(reply);
}
public static bool SetMode(RWMode value)
{
modeStr = value.ToString();
mode = value;
return(true);
}
private void ExceptionHandler(System.Runtime.InteropServices.COMException ce, RWMode rw)
{
// this is only called from the Read() call if a COM exception is raised - assume it is not catastrophic and move on
if (rw == RWMode.Read)
{
Console.Write("LOST COM READ ");
}
else
{
Console.Write("LOST COM WRITE ");
}
Console.WriteLine("Last command: " + lastCmd);
Console.WriteLine("COM Exception type " + ce.ErrorCode.ToString(CultureInfo.InvariantCulture));
{
// else if ( ve.ErrorCode = VisaStatus.ErrorTimeout && rw == RWMode.Read )
// timed out on a read - may be bacause the query data wasn't available
// or that something is up with the visa connection.
// Assume its not a catastrophic event and try to continue on
if (!HandleVisaExceptions)
{
throw ce;
}
}
}
public static extern MMIOError Advance(
IntPtr hmmio,
[In, Out, MarshalAs(UnmanagedType.LPStruct)] MMIOINFO pmmioinfo,
RWMode fuAdvance);
