CPU I/O communication part 2
- by b-gen-jack-o-neill
Hi, I was suggested when I have some further questions on my older ones, to create newer Question and reffer to old one. So, this is the original question: CPU I/O communication
OK, I have just 2 more questions.
1, How is MMIO set? I mean, lets say I have developed some extension card with PCI interface. How do you say to memory controller to redirect desired memory space to my card´s RAM? I mean, I think standart text-mode VGA MMIO adress is 0x8000. Is this HW set (every motherboard automatically redirects 0x8000 adress to PCI-E) or its just standart and can be changed (VGA says to motherboard: give me memory mapped IO at 0x8000)
2, Can one expansion card have more MMIO connections? I mean, lets say I have card with 10 Bytes of RAM. Can Bytes 0-4 be mapped to 0x0 and bytes 5-9 to 0x5000?
Please, if you know about some good article about this, please post link. Thanks.