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Correct markdown

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Mathieu Maret 2017-01-28 23:44:16 +01:00
parent 6e2f3fbd06
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Readme.md
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@ -1,22 +1,25 @@
== Instruction == # Instruction
Build with Build with
nasm -f bin mbr.asm -o mbr `nasm -f bin mbr.asm -o mbr`
Run with Run with
qemu-system-x86_64 -boot a -fda mbr `qemu-system-x86_64 -boot a -fda mbr`
Debug with Debug with
qemu-system-x86_64 -boot a -fda mbr -s -S `qemu-system-x86_64 -boot a -fda mbr -s -S`
gdb then
`gdb`
```
target remote localhost:1234 target remote localhost:1234
layout asm layout asm
b *0x7c00 b *0x7c00
c c
```
== ASM reg == # ASM reg
=== In 16 bits === ## In 16 bits
There is 4 main 16bits reg: AX, BX, CX, DX. There is 4 main 16bits reg: AX, BX, CX, DX.
You can access the 8 MSB from AX with AH and the 8 LSB with AL.( BH,BL, CH, CL) You can access the 8 MSB from AX with AH and the 8 LSB with AL.( BH,BL, CH, CL)
@ -26,32 +29,33 @@ SP is stack pointer, BP is base pointer
AX(AH, AL), BX(BH, BL), CX(CH, CL), DX(DH, DL), SI, DI, SP, BP AX(AH, AL), BX(BH, BL), CX(CH, CL), DX(DH, DL), SI, DI, SP, BP
=== In 32bits === ## In 32bits
Main register are "Extended" to 32bits but 16bits of 8bits direct access is not possible anymore. Main register are "Extended" to 32bits but 16bits of 8bits direct access is not possible anymore.
EAX, EBX, ECX, EDX, ESI, EDI, ESP, EBP EAX, EBX, ECX, EDX, ESI, EDI, ESP, EBP
=== In 64bits === ## In 64bits
Prefixed by R Prefixed by R
RAX, RBX, RCX, RDX, RSI, RDI, RSP, RBP RAX, RBX, RCX, RDX, RSI, RDI, RSP, RBP
== Bios Memory == # Bios Memory
Address range | Description
0x0 - 0x03FF ;IVT ----------------------- | -----------------------
0x400 - 0x4FF ;BIOS Data 0x0 - 0x03FF |IVT
0x500 - 0x7BFF ;Unused 0x400 - 0x4FF |BIOS Data
0x7C00 - 0x7D77 ;Bootloader 0x500 - 0x7BFF |Unused
0x7E00 - 0x9FFFF ;Unused 0x7C00 - 0x7D77 |Bootloader
0xA0000 - 0xBFFFF ;Video memory 0x7E00 - 0x9FFFF |Unused
0xB0000 - 0xB7777 ;Video memory monochrome 0xA0000 - 0xBFFFF |Video memory
0xB8000 - 0xBFFFF ;Video memory color 0xB0000 - 0xB7777 |Video memory monochrome
0xC0000 - 0xC7FFF ;BIOS ROM 0xB8000 - 0xBFFFF |Video memory color
0x80000 - 0xEFFFF ;BIOS shadow memory 0xC0000 - 0xC7FFF |BIOS ROM
0xF0000 - 0xFFFFF ;BIOS System 0x80000 - 0xEFFFF |BIOS shadow memory
0xF0000 - 0xFFFFF |BIOS System
== Interrupt Vector Table == # Interrupt Vector Table
INT_NUM | Short Description PM INT_NUM | Short Description PM
----------- | ---------------------- ----------- | ----------------------
0x00 | Division by zero 0x00 | Division by zero
@ -74,8 +78,8 @@ INT_NUM | Short Description PM
0x11 | Alignment Check 0x11 | Alignment Check
0x12 | Machine Check 0x12 | Machine Check
0x13 | SIMD Floating-Point Exception 0x13 | SIMD Floating-Point Exception
0x14 | Virtualization Exception 0x14 | Virtualisation Exception
0x15 | Control Protection Exception 0x15 | Control Protection Exception
== BIOS IRQ == # BIOS IRQ
https://en.wikipedia.org/wiki/BIOS_interrupt_call https://en.wikipedia.org/wiki/BIOS_interrupt_call