Hello,

I have a Lexmark Optra E+ connected to the parallel port of my mainboard. It works very well, printing results are great, the only problem is, that it takes very long to process a page (about 4-6 minutes). I googled a bit and found out, that I could speed up printing, if I could make the parport use IRQ (whatever that might be).
Now I read the parport.txt from the kernel documentation and there it says, IRQs are not used by default, because it might cause problems. I did a:
# cat /proc/interrupts
CPU0 CPU1
0: 10298056 0 IO-APIC-edge timer
1: 15146 0 IO-APIC-edge i8042
8: 1 0 IO-APIC-edge rtc
9: 0 0 IO-APIC-level acpi
12: 493198 0 IO-APIC-edge i8042
14: 44008 1 IO-APIC-edge ide0
15: 24 0 IO-APIC-edge ide1
16: 633508 0 IO-APIC-level nvidia
17: 178886 0 IO-APIC-level Intel ICH5
18: 14 0 IO-APIC-level aic7xxx
20: 377644 0 IO-APIC-level eth0
NMI: 0 0
LOC: 10254700 10254802
ERR: 0
MIS: 0

And it shows, that I have plenty of unused IRQ's. I now tryed to load the parport_pc modules with custom IRQ sinsmod /lib/modules/2.6.8.1/kernel/drivers/parport/parport_pc.ko io=0x3bc irq=7
ettings:
This works and will show the parport using IRQ 7, but then the printer will not print. I guess the problem is the wrong io parameter, but I have no idea which one to use. I got this form the kernel documentation, but I do not understand what it might mean. Can anyone tell me which value to choose, or what this value is and how to find the "right" one?

Thank you for your time,

cccc828

You can't just pick an IRQ at random to use with your printer. You need to use the settings that get assigned to the parallel port by the BIOS. This is usually listed when the computer starts up or by going into the BIOS to view settings.

Having said that, IRQ 7 is commonly used for parallel ports, so this may be another issue.

Having searched TLDP , I found this:
You're not using plip but these look like fairly standard numbers to me. I also remember 0x220 cropping up a lot.

Also, I'm not sure that you need to pass the IRQ to the command-line; I'm pretty sure you can set it by using something like:
Hope that's of some help,

—Robert J. Lee

Hello,

Thank you for your reply. I gave it a short try, but it did not work. Unfortunately I am in a hurry and do not have time to try more today. I will give it some more tries during the Weekend and post, if I could get it working :-)

cccc828

It is quite some time since my post, but I finally resolved the issue:
Instead of using the (recommended) hpijs driver I now use the gutenprint driver. They work just as well and are a lot faster.

cccc828

There are also some optimizations possible in the kernel configuration that have to do with transfer types and hardware support that may help.