Good day. I am new here, but I could not find answer to my question using google, so I help I do not violate any rules.

So, basically, all I want to ask is, how CPU comminucates with other HW, such as printers, Graphic card, sound card, LAN card etc.

I know, that for basic system I/O, you can use BIOS interrupts. INT 10h I believe is for display output. But, what I would like to know is, what actually happens when you execute instruction int 10h. From desription of int instruction, it should jump to routine, which is stored on adress pointed by adress stored in iterrupt table.

But how does this routine get into the RAM? Does BIOS save that routines to the RAM? And what actually that routine does? I mean, CPU can only acess RAM, right? So how can now acess some other HW? Is there some special instrucion for it? Or is CPU somehow connected to BIOS, and than BIOS actually does the work? And the last thing, does even OS like Windows or GNU/Linux use BIOS interrupts, or can OS acess HW directly? Thanks.