119 lines
1.7 KiB
NASM
119 lines
1.7 KiB
NASM
cpu 8086
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org 0x0000
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db 0x55, 0xAA
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optrom_length:
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db 0x00
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jmp optrom_init
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str_vendor:
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db "Nero", 0
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align 16
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str_product:
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db "Nero DOS", 0
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times (0x1A - ($-$$)) db 0
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dw pnp
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align 16
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pnp:
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db "$PnP"
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db 1 ; version 1
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db 2 ; 2 * 16 length
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dw 0 ; offset of next header
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db 0
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db 0 ; checksum (filled by fix-rom)
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dd 0 ; device identifier
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dw str_vendor ; manufacturer string
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dw str_product ; product name string
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db 0,0,0 ; device type string
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db 0x20 ; device indicator, bit for "read cacheable" set
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dw 0 ; boot connection vector
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dw 0 ; boot disconnect vector
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dw start ; bootstrap entry point
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dw 0 ; reserved
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dw 0
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align 16
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optrom_init:
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xor ax, ax
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mov es, ax
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mov di, 0x0060 ; vector (0x18 * 4 bytes)
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mov ax, start
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stosw
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mov ax, cs
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stosw
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retf
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putc:
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push bx
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push cx
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mov ah, 0x0e
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mov bx, 0x0000
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int 0x10
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pop cx
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pop bx
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ret
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announce:
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push cs
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mov ax, str_product
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push ax
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call printf
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db "%S (CS=%Xh)", 0x0A, 0x0D, 0x00
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add sp, 4
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ret
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start:
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mov ax, cs
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mov ds, ax
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call announce
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; clear memory until 0x01000
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xor ax, ax
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mov es, ax
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mov di, 0x500
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mov cx, 0xB00
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rep stosb
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call intr_init
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sti
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sub sp, 0x10
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mov si, sp
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mov word [ss:si+0x00], 0
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mov word [ss:si+0x02], 1
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mov word [ss:si+0x04], 0
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mov word [ss:si+0x06], 0x2000
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mov word [ss:si+0x08], 0x07fc
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mov word [ss:si+0x0A], 0
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mov word [ss:si+0x0C], 0
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mov word [ss:si+0x0E], 0
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mov ah, 0x42
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push ss
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pop ds
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call ramdisk_io
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push ax
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call printf
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db "AX=%X", 0x0A, 0x0D, 0x00
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pop ax
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add sp, 0x10
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.halt:
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hlt
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jmp .halt
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%include "ramdisk.inc"
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%include "printf.inc"
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%include "intr.asm"
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%include "debug.asm"
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%include "kprintf.asm"
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%include "dosapi.asm"
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_reloc_end:
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align 512 |