Parallel printers fail to work on kernels >2.6.9 [SOLVED]

[DaneM]

Hello, everybody.

I've been trying to upgrade to a newer kernel, and everything works fine, except that when I boot into the new kernel, my parallel printers no longer work properly. No matter which printer I use (HP LaserJet 5P or HP DeskJet 990cxi), and no matter what I'm printing, or from which program, all I get is a couple lines of gibberish printed on every page until I either do a "killall -KILL parallel" or remove the paper from the printer. /dev/lp0 exists, but if I try to echo or cat something to it, the light on the printer blinks one or two times, and then nothing at all prints.

Here is the output of lsmod:

[NeddySeagoon]

DaneM,

Hve you set up support for ECP in the kernel ?
Both those pronters you have need bi-directional support over the parallel port, so setting up a standard output only won't work.

The LaserJet 5P should understand an ASCII data stream but will want a new page command to actually put the text on the paper, so the cat test may well fail.
The DeskJet 990cxi will not understand ASCII at all. It needs a raster image. The cat test will always fail on this printer.

I assume you use PostScript with the 5P and Ghostscript with the 990cxi ?
_________________
Regards,

NeddySeagoon

Computer users fall into two groups:-
those that do backups
those that have never had a hard drive fail.

[DaneM]

Thanks for the reply!

I think I've fixed the problem, although it prints kind-of slowly. I'm not sure whether I'm using the postscript driver or not; it's the HPIJS driver. How can I tell? If I'm not using the PS driver, how cat I get it?

Here's how I got it to print (albeit slowly):

I set the kernel options as follows:

Parallel Printer Support:
<M> Parallel port support
<M> PC-style hardware
< > Multi-IO cards (parallel and serial)
[*] Use FIFO/DMA if available (EXPERIMENTAL)
[ ] SuperIO chipset support (EXPERIMENTAL)
[*] IEEE 1284 transfer modes

Character devices:
<M> Parallel printer support

Plug and Play Support:
[*] Plug and Play support
[ ] PnP Debug Messages
[ ] Plug and Play ACPI support (EXPERIMENTAL)

The two major changes are that SuperIO is now disabled, as is Plug and Play ACPI support.

I'm not sure which change really did it; I'll be tweaking it a bit more soon.

Any ideas?

Thanks.

--Dane

[NeddySeagoon]

DaneM,

Your Laser Priter has a built in PostScript interpreter, so it should print as fast in Linux as it Does in Windows, provided you send it PostScript output. There is no need to rasterise the pages in the PC first.
Linux apps all produce PostScript.

Your colour printer does not understand PostScript, so everthing must be rasterised first. Windows does a hack - it does not allow arbitary scaling of the image, so it can print quickly. Linux has to start from PostScript anyway. As the rasterising is done in the computer, printing is slow. The up side is that you get a PostScript colour printer.

To see whats happening, look in the CUPS log. If it mentions Ghostscript, then the CPU doing PostScript to raster converstion.
_________________
Regards,

NeddySeagoon

Computer users fall into two groups:-
those that do backups
those that have never had a hard drive fail.

[DaneM]

Thanks again for your reply; you seem to know a lot about printers!

I used kprinter to change the driver from postscript to ESP, and now it prints like in Windows. What's the differerce, and why is this working right now?

Thanks.

--Dane

[NeddySeagoon]

DaneM,

I don't know kprinter but I suspect the difference is that one driver does the rasterising in the computer, the other sends the PostScript straight to the printer. The latter is much faster, since no processing is involved.
_________________
Regards,

NeddySeagoon

Computer users fall into two groups:-
those that do backups
those that have never had a hard drive fail.

[DaneM]

Thanks for the replies.

I'm glad we got that solved.

Cheers!

--Dane

[v8elvis]