[Discuss] Parallel ports

[Rick Morris]

I _think_ that you have to connect something like a printer to the parallel 
port to get /dev/lp0 to show up, don't you? At least that's what it looks 
like dmesg is saying on my system (kubuntu)

Is there a /dev/parport0? Can you use that?

What shows up in /proc/devices?
I show (among others)
  6 lp
 99 ppdev

which means they show up in /dev/ as 
$ ls -l /dev/lp0
crw-rw---- 1 root lp 6, 0 2006-09-25 21:43 /dev/lp0
$ ls -l /dev/parport0
crw-rw---- 1 root lp 99, 0 2006-09-25 21:43 /dev/parport0

You can always create lp0 yourself, 
$ mknod /dev/lp0 c 6 0

I've yet to get udev to create anything the way I want (or perhaps expect is 
more accurate!).

Rick Morris

On Wednesday 27 September 2006 17:37, Hans Oeste wrote:
> I've built a parrallel port programmer for a small eeprom type chip.
> Unfortunately the machine I'm trying to run the software on, which is Linux
> software, seems to have a bum parallel port.  One of the signal lines
> appears to be dead.
>
> So I've tried to run the software on several laptops;  an IBM T42 and a
> Compaq EVO N610.  .dmesg states that a parrallel port exists, but under
> /dev there is no lp0 generated by udev.  I have also gone out and bought a
> PCI card with a parallel port on it to have the same thing happen.  No
> /dev/lp0. Unfortunately the software, written in 2004 has hardcoded port
> address assignments, although those are easy to change, at first glance and
> then a recompile to sort that part out.  It also appears to require access
> to lp0 or the programmer software dies very indignantly.
>
> Has anyone any suggestions to do with generating a /dev/lp0?
>
> Hans-Peter Oeste
> VE7OES
>