Hello,
I am just writing a method with C# programming, it need send/read content via a RS485 port. It will be failed with the exception "Exception from HRESULT: 0x80040015". When I debug the method, I found that this exception is occured in Read. the big different in the method is the serial communication instance initial once, and use it send/read more time. then release it. this method will beused 3 times. and each send command about 256 characters, the receive conntent about 1000 characters, I am not sure if it is caused by buffer in PC. but I have use the serial.flush() to cleare the buffer...
the exception:
System.Runtime.InteropServices.COMException (0x80040015): Exception from HRESULT: 0x80040015
at Ivi.Visa.Interop.IMessage.ReadString(Int32 count)
the method:
...
rm = new ResourceManager();
msg= (IMessage)rm.Open("ASRL3::INSTR", AccessMode.NO_LOCK, 0, "");
msg.TerminationCharacter = (byte)'$';
msg.TerminationCharacterEnabled = false;
ISerial serial = (ISerial)msg;
//Configure baudrate of com. port
serial.BaudRate = 115200;
serial.DataBits = 8;
serial.Timeout = 2;
serial.SetBufferSize(Ivi.Visa.Interop.BufferMask.IO_IN_AND_OUT_BUFS, 65000);
msg.WriteString(string.Concat(initial_cmd, "\r"));
System.Threading.Thread.Sleep(500);
string initialresult = msg.ReadString(1024);
....
serial.Flush(Ivi.Visa.Interop.BufferMask.IO_IN_AND_OUT_BUFS, true);
msg.WriteString(string.Concat(cmd1, "\r"));
System.Threading.Thread.Sleep(500);
string initialresult = msg.ReadString(1024);
....
serial.Flush(Ivi.Visa.Interop.BufferMask.IO_IN_AND_OUT_BUFS, true);
msg.WriteString(string.Concat(cmd2, "\r"));
System.Threading.Thread.Sleep(500);
string initialresult = msg.ReadString(1024);
....
serial.Flush(Ivi.Visa.Interop.BufferMask.IO_IN_AND_OUT_BUFS, true);
....
System.Runtime.InteropServices.Marshal.FinalReleaseComObject(msg);
Thanks for your analysis in advance!
