Sampling Rate for K8055

How can I find out what the sampling rate is for the ADC. It seems to me it is only 40 samples per second and I thought it would be much faster. If it is 40 samples per second it means the highest frequency I can take in on the analogue input is 20Hz.

The sampling interval is limited by the USB communication speed to 10ms (100 samples per second).
Here my test code and the resulting captured waveform of 20Hz sine input:

procedure TForm1.Button8Click(Sender: TObject); var i:integer; data:integer; begin Memo1.Clear; for i:=0 to 100 do begin data:=ReadAnalogChannel(1); memo1.lines.add(inttostr(data)); end; memo1.SelectAll; memo1.CopyToClipboard; end;

Thank you very much for your swift and informative answer. The answer seems obvious when somebody tells you. Thanks again