# 1 "start32H2.S" # 1 "start32H2.S" 1 # 1 "" 1 # 1 "start32H2.S" 2 #------------------------------------------------------------------------------ #* #* Copyright (c) 2006 - 2007, Intel Corporation. All rights reserved.
#* This program and the accompanying materials #* are licensed and made available under the terms and conditions of the BSD License #* which accompanies this distribution. The full text of the license may be found at #* http: #* #* THE PROGRAM IS DISTRIBUTED UNDER THE BSD LICENSE ON AN "AS IS" BASIS, #* WITHOUT WARRANTIES OR REPRESENTATIONS OF ANY KIND, EITHER EXPRESS OR IMPLIED. #* #* start32.asm #* #* Abstract: #* #------------------------------------------------------------------------------ #.MODEL small .stack: .486p: .code: .equ FAT_DIRECTORY_ENTRY_SIZE, 0x020 .equ FAT_DIRECTORY_ENTRY_SHIFT, 5 .equ BLOCK_SIZE, 0x0200 .equ BLOCK_MASK, 0x01ff .equ BLOCK_SHIFT, 9 .org 0x0 .global _start _start: Ia32Jump: jmp BootSectorEntryPoint # JMP inst - 3 bytes nop OemId: .ascii "INTEL " # OemId - 8 bytes SectorSize: .word 0 # Sector Size - 2 bytes SectorsPerCluster: .byte 0 # Sector Per Cluster - 1 byte ReservedSectors: .word 0 # Reserved Sectors - 2 bytes NoFats: .byte 0 # Number of FATs - 1 byte RootEntries: .word 0 # Root Entries - 2 bytes Sectors: .word 0 # Number of Sectors - 2 bytes Media: .byte 0 # Media - 1 byte SectorsPerFat16: .word 0 # Sectors Per FAT for FAT12/FAT16 - 2 byte SectorsPerTrack: .word 0 # Sectors Per Track - 2 bytes Heads: .word 0 # Heads - 2 bytes HiddenSectors: .long 0 # Hidden Sectors - 4 bytes LargeSectors: .long 0 # Large Sectors - 4 bytes #****************************************************************************** #The structure for FAT32 starting at offset 36 of the boot sector. (At this point, #the BPB/boot sector for FAT12 and FAT16 differs from the BPB/boot sector for FAT32.) #****************************************************************************** SectorsPerFat32: .long 0 # Sectors Per FAT for FAT32 - 4 bytes ExtFlags: .word 0 # Mirror Flag - 2 bytes FSVersion: .word 0 # File System Version - 2 bytes RootCluster: .long 0 # 1st Cluster Number of Root Dir - 4 bytes FSInfo: .word 0 # Sector Number of FSINFO - 2 bytes BkBootSector: .word 0 # Sector Number of Bk BootSector - 2 bytes Reserved: .fill 12,1,0 # Reserved Field - 12 bytes PhysicalDrive: .byte 0 # Physical Drive Number - 1 byte Reserved1: .byte 0 # Reserved Field - 1 byte Signature: .byte 0 # Extended Boot Signature - 1 byte VolId: .ascii " " # Volume Serial Number - 4 bytes FatLabel: .ascii "Clover " # Volume Label - 11 bytes FileSystemType: .ascii "HFSPlus " # File System Type - 8 bytes BootSectorEntryPoint: #ASSUME ds:@code #ASSUME ss:@code # ds = 1000, es = 2000 + x (size of first cluster >> 4) # cx = Start Cluster of EfiLdr # dx = Start Cluster of Efivar.bin # Re use the BPB data stored in Boot Sector movw $0x7c00, %bp JumpFarInstruction: .byte 0xea JumpOffset: .word 0x200 JumpSegment: .word 0x2000 # 107 "start32H2.S" .org 0x01fa # Will cause build break LBAOffsetForBootSector: .long 0x0 .org 0x01fe # Will cause build break .word 0xaa55 #****************************************************************************** #****************************************************************************** #****************************************************************************** .equ DELAY_PORT, 0x0ed # Port to use for 1uS delay .equ KBD_CONTROL_PORT, 0x060 # 8042 control port .equ KBD_STATUS_PORT, 0x064 # 8042 status port .equ WRITE_DATA_PORT_CMD, 0x0d1 # 8042 command to write the data port .equ ENABLE_A20_CMD, 0x0df # 8042 command to enable A20 .org 0x200 # Will cause build break? lol .code16 jmp start #Em64String: # .byte 'E', 0x0c, 'm', 0x0c, '6', 0x0c, '4', 0x0c, 'T', 0x0c, ' ', 0x0c, 'U', 0x0c, 'n', 0x0c, 's', 0x0c, 'u', 0x0c, 'p', 0x0c, 'p', 0x0c, 'o', 0x0c, 'r', 0x0c, 't', 0x0c, 'e', 0x0c, 'd', 0x0c, '!', 0x0c Label: .ascii "Clover " # Bootloader Label start: movw %cs, %ax movw %ax, %ds movw %ax, %es movw %ax, %ss movw $MyStack, %sp # mov ax,0b800h # mov es,ax # mov byte ptr es:[160],'a' # mov ax,cs # mov es,ax # movw $0xb800, %ax # movw %ax, %es # movw $0x61, byte ptr %es:[160] # movw %cs, %ax # movw %ax, %es # 239 "start32H2.S" movl $0, %ebx leal MemoryMap, %edi MemMapLoop: movl $0xe820, %eax movl $20, %ecx #WIKI said $24 movl $0x534d4150, %edx # 0x534d4150 = 'SMAP' int $0x15 jc MemMapDone addl $20, %edi cmpl $0, %ebx je MemMapDone jmp MemMapLoop MemMapDone: leal MemoryMap, %eax subl %eax, %edi # Get the address of the memory map movl %edi, MemoryMapSize # Save the size of the memory map xorl %ebx, %ebx movw %cs, %bx # BX=segment shll $4, %ebx # BX="linear" address of segment base leal GDT_BASE(%ebx), %eax # EAX=PHYSICAL address of gdt movl %eax, gdtr + 2 # Put address of gdt into the gdtr leal IDT_BASE(%ebx), %eax # EAX=PHYSICAL address of idt movl %eax, idtr + 2 # Put address of idt into the idtr leal MemoryMapSize(%ebx), %edx # Physical base address of the memory map addl $0x1000, %ebx # Source of EFI32 = $0x21000 movl %ebx, JUMP+2 addl $0x1000, %ebx movl %ebx, %esi # Source of EFILDR32 = $0x22000 # mov ax,0b800h # mov es,ax # mov byte ptr es:[162],'b' # mov ax,cs # mov es,ax # movw $0xb800, %ax # movw %ax, %es # movw $0x62, byte ptr %es:[162] # movw %cs, %ax # movw %ax, %es # Enable A20 Gate movw $0x2401, %ax # Enable A20 Gate int $0x15 jnc A20GateEnabled # Jump if it succeeded # If INT 15 Function 2401 is not supported, then attempt to Enable A20 manually. #New algo from WIKI # 322 "start32H2.S" #UEFI/DUET call Empty8042InputBuffer # Empty the Input Buffer on the 8042 controller jnz Timeout8042 # Jump if the 8042 timed out outw %ax, $DELAY_PORT # Delay 1 uS movb $WRITE_DATA_PORT_CMD, %al # 8042 cmd to write output port outb %al, $KBD_STATUS_PORT # Send command to the 8042 call Empty8042InputBuffer # Empty the Input Buffer on the 8042 controller jnz Timeout8042 # Jump if the 8042 timed out movb $ENABLE_A20_CMD, %al # gate address bit 20 on outb %al, $KBD_CONTROL_PORT # Send command to thre 8042 call Empty8042InputBuffer # Empty the Input Buffer on the 8042 controller movw $25, %cx # Delay 25 uS for the command to complete on the 8042 Delay25uS: outw %ax, $DELAY_PORT # Delay 1 uS loopl Delay25uS Timeout8042: #WIKI -fast A20gate # inb $0x92, %al # orb $2, %al # outb %al, $0x92 A20GateEnabled: # movw $0x0002, %ax # int $0x10 #put char 7 movl $0x000F, %ebx movl $0x0E37, %eax movl $0x0010, %ecx int $0x10 #PAUSE1: # jmp PAUSE1 # DISABLE INTERRUPTS - Entering Protected Mode movw $0x0008, %bx # Flat data descriptor cli .byte 0x66 lgdt gdtr #PAUSE2: # jmp PAUSE2 # .byte 0x67 .byte 0x66 lidt idtr #PAUSE3: # jmp PAUSE3 movl %cr0, %eax orb $1, %al # .byte 0x66 # or $1, %eax movl %eax, %cr0 # now 32-bit protected mode #.code32 # movl $0x008, %eax # Flat data descriptor # movl $0x00400000, %ebp # Destination of EFILDR32 # movl $0x00070000, %ebx # Length of copy JUMP: # jmp far 0010:00020000 .byte 0x66 .byte 0xea .long 0x00020000 .word 0x0010 Empty8042InputBuffer: movw $0, %cx Empty8042Loop: outw %ax, $DELAY_PORT # Delay 1us inb $KBD_STATUS_PORT, %al # Read the 8042 Status Port andb $0x2, %al # Check the Input Buffer Full Flag loopnz Empty8042Loop # Loop until the input buffer is empty or a timout of 65536 uS ret # 431 "start32H2.S" ############################################################################## # data ############################################################################## .p2align 1 gdtr: .word GDT_END - GDT_BASE - 1 .long 0 # (GDT base gets set above) ############################################################################## # global descriptor table (GDT) ############################################################################## .p2align 1 GDT_BASE: # null descriptor .equ NULL_SEL, .-GDT_BASE .word 0 # limit 15:0 .word 0 # base 15:0 .byte 0 # base 23:16 .byte 0 # type .byte 0 # limit 19:16, flags .byte 0 # base 31:24 # linear data segment descriptor .equ LINEAR_SEL, .-GDT_BASE .word 0xFFFF # limit 0xFFFFF .word 0 # base 0 .byte 0 .byte 0x92 # present, ring 0, data, expand-up, writable .byte 0xCF # page-granular, 32-bit .byte 0 # linear code segment descriptor .equ LINEAR_CODE_SEL, .-GDT_BASE .word 0xFFFF # limit 0xFFFFF .word 0 # base 0 .byte 0 .byte 0x9A # present, ring 0, data, expand-up, writable .byte 0xCF # page-granular, 32-bit .byte 0 # system data segment descriptor .equ SYS_DATA_SEL, .-GDT_BASE .word 0xFFFF # limit 0xFFFFF .word 0 # base 0 .byte 0 .byte 0x92 # present, ring 0, data, expand-up, writable .byte 0xCF # page-granular, 32-bit .byte 0 # system code segment descriptor .equ SYS_CODE_SEL, .-GDT_BASE .word 0xFFFF # limit 0xFFFFF .word 0 # base 0 .byte 0 .byte 0x9A # present, ring 0, data, expand-up, writable .byte 0xCF # page-granular, 32-bit .byte 0 # spare segment descriptor .equ SPARE3_SEL, .-GDT_BASE .word 0 # limit 0xFFFFF .word 0 # base 0 .byte 0 .byte 0 # present, ring 0, data, expand-up, writable .byte 0 # page-granular, 32-bit .byte 0 # spare segment descriptor .equ SPARE4_SEL, .-GDT_BASE .word 0 # limit 0xFFFFF .word 0 # base 0 .byte 0 .byte 0 # present, ring 0, data, expand-up, writable .byte 0 # page-granular, 32-bit .byte 0 # spare segment descriptor .equ SPARE5_SEL, .-GDT_BASE .word 0 # limit 0xFFFFF .word 0 # base 0 .byte 0 .byte 0 # present, ring 0, data, expand-up, writable .byte 0 # page-granular, 32-bit .byte 0 GDT_END: .p2align 1 idtr: .word IDT_END - IDT_BASE - 1 .long 0 # (IDT base gets set above) ############################################################################## # interrupt descriptor table (IDT) # Note: The hardware IRQ's specified in this table are the normal PC/AT IRQ # mappings. This implementation only uses the system timer and all other # IRQs will remain masked. The descriptors for vectors 33+ are provided # for convenience. ############################################################################## #idt_tag db "IDT",0 .p2align 1 IDT_BASE: # divide by zero (INT 0) .equ DIV_ZERO_SEL, .-IDT_BASE .word 0 # offset 15:0 .word SYS_CODE_SEL # selector 15:0 .byte 0 # 0 for interrupt gate .byte 0x0e | 0x80 # type = 386 interrupt gate, present .word 0 # offset 31:16 # debug exception (INT 1) .equ DEBUG_EXCEPT_SEL, .-IDT_BASE .word 0 # offset 15:0 .word SYS_CODE_SEL # selector 15:0 .byte 0 # 0 for interrupt gate .byte 0x0e | 0x80 # type = 386 interrupt gate, present .word 0 # offset 31:16 # NMI (INT 2) .equ NMI_SEL, .-IDT_BASE .word 0 # offset 15:0 .word SYS_CODE_SEL # selector 15:0 .byte 0 # 0 for interrupt gate .byte 0x0e | 0x80 # type = 386 interrupt gate, present .word 0 # offset 31:16 # soft breakpoint (INT 3) .equ BREAKPOINT_SEL, .-IDT_BASE .word 0 # offset 15:0 .word SYS_CODE_SEL # selector 15:0 .byte 0 # 0 for interrupt gate .byte 0x0e | 0x80 # type = 386 interrupt gate, present .word 0 # offset 31:16 # overflow (INT 4) .equ OVERFLOW_SEL, .-IDT_BASE .word 0 # offset 15:0 .word SYS_CODE_SEL # selector 15:0 .byte 0 # 0 for interrupt gate .byte 0x0e | 0x80 # type = 386 interrupt gate, present .word 0 # offset 31:16 # bounds check (INT 5) .equ BOUNDS_CHECK_SEL, .-IDT_BASE .word 0 # offset 15:0 .word SYS_CODE_SEL # selector 15:0 .byte 0 # 0 for interrupt gate .byte 0x0e | 0x80 # type = 386 interrupt gate, present .word 0 # offset 31:16 # invalid opcode (INT 6) .equ INVALID_OPCODE_SEL, .-IDT_BASE .word 0 # offset 15:0 .word SYS_CODE_SEL # selector 15:0 .byte 0 # 0 for interrupt gate .byte 0x0e | 0x80 # type = 386 interrupt gate, present .word 0 # offset 31:16 # device not available (INT 7) .equ DEV_NOT_AVAIL_SEL, .-IDT_BASE .word 0 # offset 15:0 .word SYS_CODE_SEL # selector 15:0 .byte 0 # 0 for interrupt gate .byte 0x0e | 0x80 # type = 386 interrupt gate, present .word 0 # offset 31:16 # double fault (INT 8) .equ DOUBLE_FAULT_SEL, .-IDT_BASE .word 0 # offset 15:0 .word SYS_CODE_SEL # selector 15:0 .byte 0 # 0 for interrupt gate .byte 0x0e | 0x80 # type = 386 interrupt gate, present .word 0 # offset 31:16 # Coprocessor segment overrun - reserved (INT 9) .equ RSVD_INTR_SEL1, .-IDT_BASE .word 0 # offset 15:0 .word SYS_CODE_SEL # selector 15:0 .byte 0 # 0 for interrupt gate .byte 0x0e | 0x80 # type = 386 interrupt gate, present .word 0 # offset 31:16 # invalid TSS (INT 0ah) .equ INVALID_TSS_SEL, .-IDT_BASE .word 0 # offset 15:0 .word SYS_CODE_SEL # selector 15:0 .byte 0 # 0 for interrupt gate .byte 0x0e | 0x80 # type = 386 interrupt gate, present .word 0 # offset 31:16 # segment not present (INT 0bh) .equ SEG_NOT_PRESENT_SEL, .-IDT_BASE .word 0 # offset 15:0 .word SYS_CODE_SEL # selector 15:0 .byte 0 # 0 for interrupt gate .byte 0x0e | 0x80 # type = 386 interrupt gate, present .word 0 # offset 31:16 # stack fault (INT 0ch) .equ STACK_FAULT_SEL, .-IDT_BASE .word 0 # offset 15:0 .word SYS_CODE_SEL # selector 15:0 .byte 0 # 0 for interrupt gate .byte 0x0e | 0x80 # type = 386 interrupt gate, present .word 0 # offset 31:16 # general protection (INT 0dh) .equ GP_FAULT_SEL, .-IDT_BASE .word 0 # offset 15:0 .word SYS_CODE_SEL # selector 15:0 .byte 0 # 0 for interrupt gate .byte 0x0e | 0x80 # type = 386 interrupt gate, present .word 0 # offset 31:16 # page fault (INT 0eh) .equ PAGE_FAULT_SEL, .-IDT_BASE .word 0 # offset 15:0 .word SYS_CODE_SEL # selector 15:0 .byte 0 # 0 for interrupt gate .byte 0x0e | 0x80 # type = 386 interrupt gate, present .word 0 # offset 31:16 # Intel reserved - do not use (INT 0fh) .equ RSVD_INTR_SEL2, .-IDT_BASE .word 0 # offset 15:0 .word SYS_CODE_SEL # selector 15:0 .byte 0 # 0 for interrupt gate .byte 0x0e | 0x80 # type = 386 interrupt gate, present .word 0 # offset 31:16 # floating point error (INT 10h) .equ FLT_POINT_ERR_SEL, .-IDT_BASE .word 0 # offset 15:0 .word SYS_CODE_SEL # selector 15:0 .byte 0 # 0 for interrupt gate .byte 0x0e | 0x80 # type = 386 interrupt gate, present .word 0 # offset 31:16 # alignment check (INT 11h) .equ ALIGNMENT_CHECK_SEL, .-IDT_BASE .word 0 # offset 15:0 .word SYS_CODE_SEL # selector 15:0 .byte 0 # 0 for interrupt gate .byte 0x0e | 0x80 # type = 386 interrupt gate, present .word 0 # offset 31:16 # machine check (INT 12h) .equ MACHINE_CHECK_SEL, .-IDT_BASE .word 0 # offset 15:0 .word SYS_CODE_SEL # selector 15:0 .byte 0 # 0 for interrupt gate .byte 0x0e | 0x80 # type = 386 interrupt gate, present .word 0 # offset 31:16 # SIMD floating-point exception (INT 13h) .equ SIMD_EXCEPTION_SEL, .-IDT_BASE .word 0 # offset 15:0 .word SYS_CODE_SEL # selector 15:0 .byte 0 # 0 for interrupt gate .byte 0x0e | 0x80 # type = 386 interrupt gate, present .word 0 # offset 31:16 # 84 unspecified descriptors, First 12 of them are reserved, the rest are avail .fill 84 * 8, 1, 0 # IRQ 0 (System timer) - (INT 68h) .equ IRQ0_SEL, .-IDT_BASE .word 0 # offset 15:0 .word SYS_CODE_SEL # selector 15:0 .byte 0 # 0 for interrupt gate .byte 0x0e | 0x80 # type = 386 interrupt gate, present .word 0 # offset 31:16 # IRQ 1 (8042 Keyboard controller) - (INT 69h) .equ IRQ1_SEL, .-IDT_BASE .word 0 # offset 15:0 .word SYS_CODE_SEL # selector 15:0 .byte 0 # 0 for interrupt gate .byte 0x0e | 0x80 # type = 386 interrupt gate, present .word 0 # offset 31:16 # Reserved - IRQ 2 redirect (IRQ 2) - DO NOT USE!!! - (INT 6ah) .equ IRQ2_SEL, .-IDT_BASE .word 0 # offset 15:0 .word SYS_CODE_SEL # selector 15:0 .byte 0 # 0 for interrupt gate .byte 0x0e | 0x80 # type = 386 interrupt gate, present .word 0 # offset 31:16 # IRQ 3 (COM 2) - (INT 6bh) .equ IRQ3_SEL, .-IDT_BASE .word 0 # offset 15:0 .word SYS_CODE_SEL # selector 15:0 .byte 0 # 0 for interrupt gate .byte 0x0e | 0x80 # type = 386 interrupt gate, present .word 0 # offset 31:16 # IRQ 4 (COM 1) - (INT 6ch) .equ IRQ4_SEL, .-IDT_BASE .word 0 # offset 15:0 .word SYS_CODE_SEL # selector 15:0 .byte 0 # 0 for interrupt gate .byte 0x0e | 0x80 # type = 386 interrupt gate, present .word 0 # offset 31:16 # IRQ 5 (LPT 2) - (INT 6dh) .equ IRQ5_SEL, .-IDT_BASE .word 0 # offset 15:0 .word SYS_CODE_SEL # selector 15:0 .byte 0 # 0 for interrupt gate .byte 0x0e | 0x80 # type = 386 interrupt gate, present .word 0 # offset 31:16 # IRQ 6 (Floppy controller) - (INT 6eh) .equ IRQ6_SEL, .-IDT_BASE .word 0 # offset 15:0 .word SYS_CODE_SEL # selector 15:0 .byte 0 # 0 for interrupt gate .byte 0x0e | 0x80 # type = 386 interrupt gate, present .word 0 # offset 31:16 # IRQ 7 (LPT 1) - (INT 6fh) .equ IRQ7_SEL, .-IDT_BASE .word 0 # offset 15:0 .word SYS_CODE_SEL # selector 15:0 .byte 0 # 0 for interrupt gate .byte 0x0e | 0x80 # type = 386 interrupt gate, present .word 0 # offset 31:16 # IRQ 8 (RTC Alarm) - (INT 70h) .equ IRQ8_SEL, .-IDT_BASE .word 0 # offset 15:0 .word SYS_CODE_SEL # selector 15:0 .byte 0 # 0 for interrupt gate .byte 0x0e | 0x80 # type = 386 interrupt gate, present .word 0 # offset 31:16 # IRQ 9 - (INT 71h) .equ IRQ9_SEL, .-IDT_BASE .word 0 # offset 15:0 .word SYS_CODE_SEL # selector 15:0 .byte 0 # 0 for interrupt gate .byte 0x0e | 0x80 # type = 386 interrupt gate, present .word 0 # offset 31:16 # IRQ 10 - (INT 72h) .equ IRQ10_SEL, .-IDT_BASE .word 0 # offset 15:0 .word SYS_CODE_SEL # selector 15:0 .byte 0 # 0 for interrupt gate .byte 0x0e | 0x80 # type = 386 interrupt gate, present .word 0 # offset 31:16 # IRQ 11 - (INT 73h) .equ IRQ11_SEL, .-IDT_BASE .word 0 # offset 15:0 .word SYS_CODE_SEL # selector 15:0 .byte 0 # 0 for interrupt gate .byte 0x0e | 0x80 # type = 386 interrupt gate, present .word 0 # offset 31:16 # IRQ 12 (PS/2 mouse) - (INT 74h) .equ IRQ12_SEL, .-IDT_BASE .word 0 # offset 15:0 .word SYS_CODE_SEL # selector 15:0 .byte 0 # 0 for interrupt gate .byte 0x0e | 0x80 # type = 386 interrupt gate, present .word 0 # offset 31:16 # IRQ 13 (Floating point error) - (INT 75h) .equ IRQ13_SEL, .-IDT_BASE .word 0 # offset 15:0 .word SYS_CODE_SEL # selector 15:0 .byte 0 # 0 for interrupt gate .byte 0x0e | 0x80 # type = 386 interrupt gate, present .word 0 # offset 31:16 # IRQ 14 (Secondary IDE) - (INT 76h) .equ IRQ14_SEL, .-IDT_BASE .word 0 # offset 15:0 .word SYS_CODE_SEL # selector 15:0 .byte 0 # 0 for interrupt gate .byte 0x0e | 0x80 # type = 386 interrupt gate, present .word 0 # offset 31:16 # IRQ 15 (Primary IDE) - (INT 77h) .equ IRQ15_SEL, .-IDT_BASE .word 0 # offset 15:0 .word SYS_CODE_SEL # selector 15:0 .byte 0 # 0 for interrupt gate .byte 0x0e | 0x80 # type = 386 interrupt gate, present .word 0 # offset 31:16 .fill 8, 1, 0 IDT_END: .p2align 1 MemoryMapSize: .long 0 MemoryMap: .long 0,0,0,0,0,0,0,0 .long 0,0,0,0,0,0,0,0 .long 0,0,0,0,0,0,0,0 .long 0,0,0,0,0,0,0,0 .long 0,0,0,0,0,0,0,0 .long 0,0,0,0,0,0,0,0 .long 0,0,0,0,0,0,0,0 .long 0,0,0,0,0,0,0,0 .long 0,0,0,0,0,0,0,0 .long 0,0,0,0,0,0,0,0 .long 0,0,0,0,0,0,0,0 .long 0,0,0,0,0,0,0,0 .long 0,0,0,0,0,0,0,0 .long 0,0,0,0,0,0,0,0 .long 0,0,0,0,0,0,0,0 .long 0,0,0,0,0,0,0,0 .long 0,0,0,0,0,0,0,0 .long 0,0,0,0,0,0,0,0 .long 0,0,0,0,0,0,0,0 .long 0,0,0,0,0,0,0,0 .long 0,0,0,0,0,0,0,0 .long 0,0,0,0,0,0,0,0 .long 0,0,0,0,0,0,0,0 .long 0,0,0,0,0,0,0,0 .long 0,0,0,0,0,0,0,0 .long 0,0,0,0,0,0,0,0 .long 0,0,0,0,0,0,0,0 .long 0,0,0,0,0,0,0,0 .long 0,0,0,0,0,0,0,0 .long 0,0,0,0,0,0,0,0 .long 0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0 .long 0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0 .org 0x0fe0 MyStack: # below is the pieces of the IVT that is used to redirect INT 68h - 6fh # back to INT 08h - 0fh when in real mode... It is 'org'ed to a # known low address (20f00) so it can be set up by PlMapIrqToVect in # 8259.c int $8 iret int $9 iret int $10 iret int $11 iret int $12 iret int $13 iret int $14 iret int $15 iret .org 0x0ffe BlockSignature: .word 0xaa55