lx0-101 what I need to know about IRQs, I/O addresses, and altering them.
 

Hey guys, I'm studying pretty hard for my first linux exam. I see that IRQ's and I/O addresses are stressed pretty hard however there is not a good amount of information out there about it. I did a couple of google searches but all the answers are more on the electrical engineering and h/w programming side of the spectrum and way over my head. Basically I only really want to know what I need to know for the lx0-101 and 102 exams.


One question I definitely however is when looking at I/O addresses the correlate with an IRQ. So basically /dev/ttys0 is associated with irq 4. TTYS0 is the first true terminal on the linux system correct? So why does it communicate with the IRQ responsible for RS-232 communication?

I understand that RS-232 is a dated technology- did they simply just determine rs-232 is not needed and let ttys0 use it's irq?

I think I'm missing a few fundamental ideas about IRQs. I'm not sure if multiple devices can communicate over one IRQ - but I do know that devices should not share IRQ's

If someone can just give me a brief lowdown to better my understanding.

Thanks a ton guys!