Issue setting baud rate for IMAQ using Camera Link

Question

I have a PCIe-1433 camera link board, with a Basler camera. I found that I can set the gain and exposure times directly in the camera using the serial link and serial commands. This works very well. I'm doing this programmatically using the CLAllSerial.DLL.
The serial commands take too long to send in my application due to the default baud rate of 9600, so I was able to send a command to the Basler camera to up its baud rate, then change the baud rate of the camera link serial com port to match it. The result is that I can talk very quickly to the camera. Sweet so far.
However, with both the Basler camera and the camera link com port set to the higher baud rate, I can no longer acquire images using the IMAQ imgXXX commands. I get a timeout from the serial commands that IMAQ must be using to control the camera for image acquisition. Essentially the IMAQ driver doesn't know about the baud rate change. I cannot see how I can tell the IMAQ driver what baud rate to use either. NI MAX also becomes unusable in this situation.
How can I, through the IMAQ driver, increase the baud rate of the serial commands to the camera over the camera link?
Cheers,
Wayne
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Answer 1

David,
I'll try to help if I can. Keep in mind that I'm using a stub into the DLL using Delphi as my development platform. That should not matter.
The DLL I'm tapped into is the IMAQ.DLL for the camera calls to get/set exposure time, gain, etc. The best reference I found for this is the NI-IMAQ help files that get installed with the normal NI install. There are important string constants that you need, to talk to the interface. I can't recall how I found these, but below are mine, in Delphi:
{ These are Basler camera attribute names we care about. }
BaslerCameraGainControlAttributeString = 'Gain'; { string result }
BaslerCameraGainValueAttributeString = 'Gain Value'; { numeric result }
BaslerCameraBitDepthAttributeString = 'Bit Depth'; { string result }
BaslerCameraExposureControlAttributeString = 'Exposure Control'; { string result }
BaslerCameraExposureModeAttributeString = 'Exposure Mode'; { string result }
BaslerCameraExposureTimeAttributeString = 'Exposure Time'; { numeric result }
BaslerCameraMaximumHeightAttributeString = 'Maximum Height'; { numeric result }
BaslerCameraPowerOverCameraLinkAttributeString = 'Power Over CameraLink'; { string result }
{ These are Basler camera attribute values we care about. }
BaslerCameraManualGainAttributeValue = 'Manual';
BaslerCamera12BitDepthAttributeValue = '12-bits';
BaslerCameraMaximumHeightAttributeValue = 2048;
BaslerCameraExposureControlFreeRunAttributeValue = 'Free Run';
BaslerCameraExposureControlTriggeredAttributeValue = 'Triggered';
BaslerCameraExposureModeAttributeValue = 'Manual';
BaslerCameraExposureTimeAttributeValue = 5;
BaslerCameraPowerOverCameraLinkAttributeValue = 'On';
BaslerCameraGainValueAttributeValueMinimum = 33;
BaslerCameraGainValueAttributeValueMaximum = 512;
MaxAttributeStringLength = 100;
The following code snippets, get and set gain and exposure times (I called it shutter speed), in Delphi:
function TNiVision.GetGain : double;
var
  TheGain : double;
begin
  if GetCameraAttributeNumeric( BaslerCameraGainValueAttributeString, TheGain ) then
    Result := TheGain
  else
    Result := BaslerCameraGainValueAttributeValueMinimum;
end;
procedure TNiVision.SetGain( TheGain : double );
begin
  SetCameraAttributeNumeric( BaslerCameraGainValueAttributeString, TheGain );
end;
function TNiVision.GetShutterSpeed : double;
var
  TheSpeed : double;
begin
  if GetCameraAttributeNumeric( BaslerCameraExposureTimeAttributeString, TheSpeed ) then
    Result := TheSpeed
  else
    Result := 1;
end;
procedure TNiVision.SetShutterSpeed( TheSpeed : double );
begin
  SetCameraAttributeNumeric( BaslerCameraExposureTimeAttributeString, TheSpeed );
end;
These then call into the DLL functions imgGetCameraAttributeNumeric and imgSetCameraAttributeNumeric. There is a formatting interface between the above and the actual DLL functions I didn't show that just reforms the Delphi strings attribute names into C null terminated char arrays.
I hope this helps. I've now moved on to using Pylon with GigE cameras, which is a much cleaner interface, but very different code.
Cheers,
Wayne