I have a K8000 card that use to control a DC motor with a refresh rate as high as possible, until 1000Hz. I work on a PC Intel Xeon 3.2 Ghz, 2 MB RAM, in Windows XP SP2 OS, controlling the card by C++ programming in Visual Studio 6 environment. Do you have any informations about the time necessary to set the value of a DAC port output? Some experiments show that this time in my case is about 50 milliseconds, that it seems too large to me. Is there any way to speed up the connection?
The k8e.exe checks the commands from the application software every 10ms.
The 1000Hz update rate is too high to achieve.
I know that k8e.exe manages the connection to PC, but how? From what does this file come? It would be possible to shorten this 10 ms period changing something in the file?
You may now download a faster k8e.exe from this link:
box.net/shared/gg7bry17gf
The timer interval is now 1ms.
I tested the operation with this code:
procedure TForm1.Button1Click(Sender: TObject);
var i:integer;
begin
for i:=0 to 100 do
begin
SetIOchannel(1);
ClearIOchannel(1);
end;
end;
This is the output measured with the new k8e.exe (1ms interval):
This is measured with the original k8e.exe (10ms interval):
Thank you for the update. In my hardware medium setting time is about 2 millisecond and reading time is about 4 millisecond for the analog ports with the new k8e.exe. Same periods are about 10 and 21 milliseconds with the old k8e.exe. I’ve noticed that my application program runs without any k8e.exe file in the application folder too, with setting and reading time equal to that with the old k8e.exe. So I’m now interested in understanding k8e.exe file, and why I should need it.
It seems that you have the old k8e.exe in the Windows\System32 folder or somewhere else where your application can find it.
The k8e.exe is needed to handle the LPT port communication. Using the DriverLinx driver (dlportio.sys and dlportio.dll) it can get direct access to the LPT port hardware. Normally this access is denied in Windows NT, Windows 2000, XP, Vista etc.
I’ve fixed my problem moving the K8000 reading and setting functions out of the callback function of my application program. Furthermore, I need to place k8e.exe and k8d.dll in the folder where executable file is.