Real Mode: Difference between revisions

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Revision as of 07:19, 21 January 2017 view source Brendan (talk \| contribs) 250 edits m Added warning ← Older edit		Latest revision as of 17:25, 23 June 2024 view source Mintsuki (talk \| contribs) Administrators 21 edits Fix nonsense stack alignment sentence away. Tag: Visual edit: Switched
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Line 47: === The Stack === SS and SP are 16-bit segment:offset registers that specify a 20-bit physical address (described above), which is the current "top" of the stack. The stack stores 16-bit words, and grows downwards~~, and must be aligned on a word (16-bit) boundary~~. It is used every time a program does a PUSH, POP, CALL, INT, or RET opcode and also when the BIOS handles any hardware interrupt. === High Memory Area === Line 118: == x86 Assembly Example == <~~source~~syntaxhighlight lang="asm"> [bits 16] Line 145: mov eax, cr0 mov [savcr0], eax ; save pmode CR0 and eax, 0x7FFFFFFe ; Disable paging bit & ~~enable~~disable 16-bit pmode. mov cr0, eax Line 160: lidt [idt_real] sti ; Restore interrupts -- be careful, unhandled int's will kill it. </syntaxhighlight> ~~</source>~~ == See Also == Line 176: ** Volume 3A: System Programming Guide, Part 1,Chapter 20:8086 EMULATION,which is a detailed reference about real mode using 32-bit addressing mode [[Category:Real Mode]] [[Category:X86]] [[Category:X86 CPU]] [[Category:Operating Modes]]