RE: [hpoj-devel] Looking into options....

[PASCHAL,DAVID (HP-Roseville,ex1) <dav...@hp...>]

Hi, Christopher.

Christopher Young wrote:
> I was curious what the current development projects are (what 
> is being 
> worked on beyond 0.7, which I pulled down code for).
There's a TODO list at http://hpoj.sourceforge.net/todo.shtml.  So far I
haven't checked anything new into CVS since I released 0.7.  At the moment
I'm concentrating on the user-mode I/O driver rewrite.  It's not quite
functional yet, and I have some legal issues to resolve before I can release
it anyway, but I hope to have both taken care of in the near future.  In
addition to the four enhancements listed under it at the bottom of the TODO
page (1284.4, USB, BSD, and PML multiplexing), it should fix at least six of
the items in the "Known bugs" list.  Stay tuned for more information...  :-)

> I am looking at 
> purchasing the HP OfficeJet G85 as my wife needs standalone 
> faxing and 
> copying.
> Would this be a good choice?  It appears to have the most 
> checks on the 
> 'supported devices' list.
I have a G85 at home and at work, and I really like it.  It definitely makes
a great standalone copier, and although I haven't had the occasion to use
the standalone fax functionality very much, I'm sure that works well too.
Printing and scanning work well for me on a non-SMP system running 2.2.18,
but there are still some driver-level issues with SMP and/or 2.4, which the
future user-mode driver should fix.  The color print quality from the
Ghostscript cdj550 driver isn't perfect, but better output may be possible
from the cdj970 driver, or from the new driver HP is demoing this week at
LinuxWorld Expo (http://news.cnet.com/news/0-1003-200-4598294.html).

> I use CUPS as the print system, so I'm a 
> little confused as to how that will work together, but I'm trying to 
> work those things out in my head (don't wanna buy the device 
> until I'm 
> sure that I can make everything work to my wife's 
> satisfaction ;) It is 
> very important to me to purchase the best all-in-one device with good 
> Linux support, so any advise on this would be much appreciated.
I'm not familiar with CUPS, but it should work as long as you can select an
appropriate Ghostscript driver (cdj550, unless you patch and recompile
Ghostscript to add cdj970) and tell it to send the output to something like
"/dev/ptal-printd/mlc_mlcpp0".  One purpose of the "ptal-printd" daemon I
introduced with 0.7 was to make printing setup with hpoj as similar as
possible to the traditional methods used for different distributions and
print spooler systems.

> On another note, I really like the idea of a user-space daemon to 
> control everything.  This would seem to provide the easiest 
> way to get 
> everything up and working.
It will also be much easier for me to maintain and port to other operating
systems, because it won't break every time an internal interface is changed
in the kernel.

> Also, what would be the best way 
> to 'browse' 
> for a ptal-printd -based printer.
I'm not sure what you mean by "browse".  First start the daemon with a
commmand line such as "ptal-printd mlc:mlcpp0 -like /dev/lp0 &".  Then tell
CUPS to set up a local print queue for a DeskJet 550 (under RedHat 6.2, I
select 24 or 32 bpp, send EOF after job, fix stair-step effect, and maybe
fast text printing), and tell it to print to "/dev/ptal-printd/mlc_mlcpp0",
instead of "/dev/lp0".  (The purpose of the "-like /dev/lp0" switch is to
tell it from where to copy ownership/permissions for the named pipe.)

> I'm asking this, before I 
> would like 
> to try making a CUPS backend for these units as well as 
> trying to figure 
> out the best PPD/CUPS filters for them.
> I would really like to see more information regarding the use of cups 
> (as well as the graphical tools, KUPS & qtcups) to configure 
> them and print.
Like I said, I'm not familiar with CUPS, so I can't give CUPS-specific
advice.  However, in the previous paragraph I briefly outlined the general
setup procedure for the case of printing through the parallel port, and more
information is available in the PRINT-HOWTO file in the source package.

I hope this helps.  Let me know if you have any further questions or
problems.

David