I try to activate my hp840c, when I realize that something miss...
root@darkstar:/home/vlada# lsmod
Module Size Used by
nvidia 6831076 22

root@darkstar:/home/vlada# modprobe parport
FATAL: Module parport not found.

Can somebody explain me why I cant run this module, how modules funcitions anyway?

What kernel version are you using? Is it the official Slackware kernel or a custom compiled kernel?

I use slackware 11, and 2.6.20 kernel

Does the problem exist with one of the official Slackware kernels? If not, then your custom kernel configuration is incomplete and/or you forgot to do a "make modules_install" after building it.

its custom kernel not from slackware.
When I compile kernel I didn't select anything like module, why, I read that modules can be turned on after in linux, but do they have to be enabled in kernel configuration? What does modules work exactly?

pS
I added peralel port support like part of kernel not module

Look at the following guide to compile your kernel
http://www.bitbenderforums.com/vb22/...?postid=296104

It gives good examples what to select as module and what not.
Helpt me a lot.

You can enable them after compiling the kernel. You enter the same kernel configuration setup, select the modules and issue the commands: make modules; make modules_install
I personally only got my parallel printer to work when using parport as module instead of built-in.

You can enable them after compiling the kernel. You enter the same kernel configuration setup, select the modules and issue the commands: make modules; make modules_install
I personally only got my parallel printer to work when using parport as module instead of built-in.

that meens that I have to again compile kernel right, create new bzImage, and restart machine?
So if I'am right, I have to select some parts in kernel like modules that I can later enable and disable them with modprobe?

No, you don't have to compile the kernel again that means, you don't need to make bzImage again.
You can simply enter kernel's configuration (make menuconfig or xconfig, as you like) select what you need as modules (with the M letter on them). You save the new configuration, and instead of making a new bzImage, you make only what you've selected as a module with the commands I told you above.
After that, you can modprobe the modules that you want, some of them will be probably loaded automatically by udev or hotplug.

If you compiled something right into the kernel (that's a * sign in the setup instead of a M) it's already loaded with the kernel.