printing problem - spurious "d" characters, bad pixels, spuriousform feeds

["Daniel B." <dsb@smart.net>]

Can anyone help with this?  I got absolutely no replies when I 
posted it before.  Now the problem is much worse, with dozens
of errors per page, maybe evening averaging one error per line 
of text (when printing a plain-text file).

Thanks.


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Since I upgraded to Debian Sarge and switched to CUPS for printing, I've
been getting lots of errors in my printouts.

The error pattern is that somewhere in the middle of the printout, there
is a spurious "d" character, and right next to the "d" (I think after it)
there is a column or two of erroneous dots.  (Sometimes after the "d" the
printer jumps to the next page.)  The printed "d" seems to be in the
printer's built-in font for plain-ASCII(+) printing.  (It's not in font
of any text in the middle of which the error occurs.)

It seems as if:
- the (non-Postscript) printer (a Canon BubbleJet 200-ex) has going along
   happily printing out the bitmap generated by gs or whatever my
   Postscript-to-printer-commands filter is,
- something got out of sync (e.g., the printer thought the bitmap data
   ended),
- the next byte was an ASCII "d",
- the printer, being back in plain-text mode, printed a "d"
- the printer got back into bitmap-printing mode, but something wasn't
   quite synchronized (thus the the next column or so of dots got messed
   up)
- things got synchronized again for a while (since the printout's fine
   until the next error.)

The location of the errors seems to be random.  Re-printing the same
document the same way (e.g., printing a text document through enscript
or printing a web page from a browser) yields errors in different locations.

I'm pretty sure it's not a cabling or printer unreliability problem.  I
haven't even unplugged the printer or printer cable (parallel) since I
upgraded from woody to sarge, and (I think) printing still prints fine
from Windows.)

I think it's a printing software problem (although I guess it could
theoretically be a kernel problem with the parallel port).  When I
upgraded from Woody to Sarge, I also switched to using CUPS from
whatever I had before, which I think involved magicfilter and using
gs as the Postscript engine.

The errors always involve a "d" character.  That makes me think that the
"d" characters I see are "d" bytes that were supposed to be partof the
frame around bitmap data, and that some count of bitmap-data bytes is
getting out of sync with the stream of bitmap-data bytes (e.g., as if an
extra bytes or bytes, or a bad count, is being generated by the
Postscript-to-bitmap renderer or an extra byte or bytes are being written
out to the printer).


Has anyone seen a problem like this?


Thanks.

Daniel



-- 
Daniel Barclay
dsb@smart.net