Hi,
        To all the PC programming experts a couple of questions.
I'm transferring data from a CCD image sensor for display on a PC via the
parallel port.  Works fine, 8 bit gray scale. 400 x 280 pixels.  I'm using a
F877 to transfer data to the PC using the parallel port in Bi-directional
mode.  On the PC end, I'm using Delphi 5 with my own Assembly Portin,
Portout, Porttest routines.  Plotting pixels using the Plotxy functions.

The problem, it's very slow.  It takes ~12 seconds to plot a frame on a
Pentium 120.  From what I've read, the maximum toggle rate I can expect on
the parallel port is 500 nsec to 2 usecs, depending on what you read.  Even
so, I'm seeing times between setting a bit on the parallel port by the F877
to the time the PC recognizes the signal of about 15 usecs.  Also,  the
plotting routine itself is slow, about 6 seconds to plot the 400 X 280 frame
when plotting a test grayscale pattern, no port IO, just incrementing the
plot value.

Does anyone have any ideas on how to speed things up?  I need a Windoze
95/98 environment using either Delphi or VB.
Any ideas on how to speed up the data transfer?  Faster portIO?  Faster
Plotting in Delphi?
It seems crazy to me that my $5.00 PIC has to wait for a 120 MHz machine to
do data transfers.  Is the Windoze environment that inefficient?

Any ideas and help is appreciated and may be useful to other group members.

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