Creating RAM partition??

[Fabrizio Grasso]

Hi all,
I'm using ARM9 S3C2410A from Samsung and Linux 2.4.18 from Mizi.

I'd like to know if it's possible ( and how :) ) to create a RAM filesystem 
which I can mount in R/W mode... at a specified RAM area.
I think I must create something under /dev path which represent the 
specified memory area and then mount it at runtime with something like:
"mount -t ramfs /dev/... /mnt/ramfs".

But... how to create the /dev/... object??

At this moment I have /dev/rd/0 which I can mount with:
"mount -t ramfs /dev/rd/0 /mnt/ramfs"
I can read/write to /mnt/ramfs but I don't know at which memory address it 
write!

PS: Probably I'm wrong in all my reasoning... if it so... please 
redirection me to the correct way!!

Thanks!