I am trying to create C# functions that will wait until the GPIB command has actually completed on the system that it is executed on. That is, I dont want to just wait until the command has been run, I want to wait until the command is complete. So for example, if I do a Device.Write(":INITiate:IMMediate" ) where the Device is a Spec A, I want to wait until the sweep is complete on the system before continuing in my code. I think the Device.Wait(IOComplete) only waits for the issuing of the command to complete. It doesnt wait for the sweep to finish (I know this because after I run Device.Write(":INITiate:IMMediate" ), then Device.Wait(IOComplete), then Device.Write(":CALCulate:MARKer:MAXimum" ), which does a peak search. And I can see that on the Spec A, that the sweep isnt complete when the peak search is executed. This is cutouts of the code I have so far. I would also like to do a similar thing with Read (that is make sure the read is finished before moving on). I feel there is a better way than what I have below (which seems to work ok, but it might just be because of the extra delay introduced by the *OPC? command. Board mGpibBoard = new Board(mGPIBConfiguration.GPIBBoardID); mGpibBoard.AbortAsynchronousIO(); mGpibBoard.SendInterfaceClear();mGpibBoard.BecomeActiveController(true); mGpibBoard.IOTimeout = GPIB_TIMEOUT_VALUE;mGpibBoard.SetEndOnEndOfString = false; mGpibBoard.SetEndOnWrite = true; Device Unit = new Device(mGPIBConfiguration.GPIBBoardID, gpibUnit.PrimaryAddress);Unit.TerminateReadOnEndOfString = false; Unit.IOTimeout = GPIB_TIMEOUT_VALUE;Unit.SerialPollResponseTimeout = GPIB_TIMEOUT_VALUE;Unit.SetEndOnEndOfString = false; Unit.SetEndOnWrite = true; public void SyncWrite(String command) { if (Unit != null) { GpibStatusFlags wait_mask = (GpibStatusFlags.IOComplete | GpibStatusFlags.Timeout); Unit.Write(command); Unit.Wait(wait_mask); bool synced = false; int counter = 0; while (!synced && counter < 100) { Unit.Write("*OPC?"); Unit.Wait(wait_mask); String val = Unit.ReadString(); Unit.Wait(wait_mask); synced = val.Trim().Replace("+","").Equals("1"); counter++; } }} public String SyncRead(String command) { String read_string = ""; if (Unit != null) { GpibStatusFlags wait_mask = (GpibStatusFlags.IOComplete | GpibStatusFlags.Timeout); Unit.Write(command); Unit.Wait(wait_mask); read_string = Unit.ReadString(); Unit.Wait(wait_mask); bool synced = false; int counter = 0; while (!synced && counter < 100) { Unit.Write("*OPC?"); Unit.Wait(wait_mask); String val = Unit.ReadString(); Unit.Wait(wait_mask); synced = val.Trim().Replace("+", "").Equals("1"); counter++; } } return read_string; } Thanks,Nick

Measurement Studio for .NET Languages

Writing C# Synchronized Read/Write Functions

Author

Hey Caleb,

The manufacturer is Lambda Americas, Inc. We told him about the delay time it takes to do a simple "STAT:QUES:COND?" (~250 to 300 ms). He thinks the worst case should be about 100ms. He thinks it might be the drivers. I sent him the same capture file I sent you and he said he'll get back to me.

Thanks,

Nick

Message 31 of 32

(1,391 Views)

Hi Nick,

Glad you were able to find out where the delay was coming from. Hopefully they will be able to get everything resolved.

Caleb W

National Instruments

Message 32 of 32

(1,384 Views)

Measurement Studio for .NET Languages

Writing C# Synchronized Read/Write Functions

Re: Writing C# Synchronized Read/Write Functions

Re: Writing C# Synchronized Read/Write Functions