[NCLUG] Re: LILO on fragile flies

[Michael Dwyer]

Rho Green wrote:
> Now if only I could get my printer working again.  I submitted a request a
> couple weeks ago concerning this printer problem that no one responded to.
> I have some new information that hopefully will help.  Here is what I'm
> seeing:
> I see an error when I boot up Linux saying that it could not open /dev/lp0.

Okay, go make sure that /dev/lp0 exists.  Then, make sure that there
is a driver attached to it.  Check to see that /proc/devices contains
a line like "  6 lp".  /proc/ioports should have a line like this 
"0378-037a : parport0"  
If these aren't there, you might be missing the drivers -- perhaps
you need to load the "lp" kernel module?  Perhaps it tried to load
and failed?  You might try "dmesg | grep lp" for hints, maybe.

> New stuff:
> I ran printtools, removed my printer, rebooted, then added my printer back
> and I get the same problem.

Wrong level.  Find out what happened to /dev/lp0, first.  Also, you
might check the permissions on /dev/lp0 -- it need to be writable by
whatever user the LPD runs as.

> I have a suspicion that my IRQ got was changed.  My machine was shut off by
> the power strip and when I turned it back on, that's when I started having
> problems.  When I booted up Windows on the same machine, it had to reload
> the driver for the printer serial port, and now it prints fine.  So, I think
> I need to do the same thing on my Linux machine, but I don't know how.

Prolly not.  Bare, boring LP access doesn't really need an IRQ.  On
my computer, an IRQ line isn't ever reserved for it.  I think Linux
runs in polling mode on parallel ports by default.  
A maybe more likely thing is that the port got turned off in your
CMOS setup -- especially if it is built into the motherboard.  
Reboot your machine an hit Delete, F1, F2, or whatever to enter
the SETUP.  (Hitting TAB or ESC can sometime get rid of the logo
so you can actually SEE the message telling you which key to press)

Once in there, check under something like Integrated Pheriferals (sp?)
for "Parallel Port" and be sure it is still set to LPT1/0x3F8 IRQ7
or something similar.  You may also be given the option to choose 
SPP, ECP, EPP, or some other three-letter-acronym.  Uhhh... good luck.
SPP is the lowest common denominator, but might not work for newer 
printers requiring read-back support...

> Thoughts? How can I check my IRQ setting on Linux? (I tried using setserial,
> but I guess I don't know how to use it :-)  I know how to check the current
> IRQ settings in Windows and can compare with Linux.

cat /proc/interrupts