primax: D600
Subject:
D600
From:
Mike Rothon ####@####.####
Date:
5 Jan 2003 17:59:30 -0000
Message-Id: <200301022137.00122.miker@mazpro.co.uk>
Yet more investigation as to why the D600 won't scan at 600 DPI...
I had originally put this down to a timing or throughput problem, but I have
now repeated the tests on 3 sets of hardware (P90, K6+ 400 and Athlon 1400)
and all have similar results.
Also the new libieee1284 version exhibits the same problem, so I don't think
that it can be timing.
Having put in extensive diagnostic statements, I am still at a loss to see
where things are going wrong. The scanner simply scans the first through
lines and then refuses to output the bit pattern needed to exit the first do
loop in get_scan_data ().
It seems that the scanner is never filling the FIFO with the necessary data
for the next scan line.
However it isn't at all clear for the reason. For example an image 2 inches
wide (command line param -d 2x11.5) will work okay at 600dpi, but not an
image 4 inches wide.
Likewise an image 4 inches wide will scan okay at 400dpi.
Another thought was a buffer overflow somewhere, but I can't find it!
So my conclusion is that the D600 has a slightly different internal FIFO
architecture, or command set. Perhaps it is necessary to scan each line in
two halves?
I think I have got to the stage whereby the only way to make this work is to
get hold of the Primax documents. So if anyone on this mailing list has a
copy I would be very grateful to receive it.
Best regards,
Mike Rothon.
