计算机接口存储讲座.pptVIP

计算机接口存取概述 讲解：王子亮 概述 PC Architecture Memory Access IO Access Super IO Access PCI Access Other Main Block of PC Mother Board GMCH ICH6 进入保护模式的步骤 1、建立全局描述符表，包括代码段、数据 段、堆栈段等等的描述符和选择子的设定 2、设置伪描述符（包括全局描述符，代码描述符，数据描述符等） 3、加载全局描述符表，打开地址线A20 4、把控制寄存器CR0的位0置为1 必须在保护模式下运行的指令集 基本串操作指令： LODSD,STOSD,MOVSD,SCANSD CMPSD IN Protect Mode: if we set BASE = 1M, and keep A20 Open, when switch to real mode, we can use 32bit OFFSET to access just only (4G-1M) Memory Space from 1M~4G IN Big Real Mode: If we close A20,then bit 20 will always be zero,so when we want to access 1M(bit 20 should be 1),but the answer we can get just is 0M and we can conclude that : 0~1M=1M~2M; 2M~3M=3M~4M; 4M~5M=5M~6M … … D12I SIO ADDRESS:INDEX=164EH DATA =164FH Super IO ReadWrite Read Register[7]: mov al,07h mov dx,164EH out dx,al mov dx,164fh in al,dx Write Register[7] : mov al,07h mov dx,164EH out dx,al mov dx,164fh out dx,03h PCI Example Overview Type 0 PCI Configuration Header PCI ReadWrite Read Register[7]: mov eax,8000e804h mov dx,0cf8H out dx,eax mov dx,0cfch in eax,dx Write Register[7] : mov eax,8000e804h mov dx,0cf8H out dx,eax mov dx,0cfch out dx,0ffh * * USB2.0 Graphics (G)MCH PCI Express* HDD PCI Memory CPU SIO SATA GbE MB Down Device PCI Express PCI Express PCI Express PCI Express Add-ins Add-ins Intel? ICH PCI Express 20bits Address Lines, 1M Space Physics: 00 0000h~0F FFFFh Access Physics Address SEG:OFF(16bits) ===? SEG4+OFF(16bits) e.g. DS:SI ====?