69 lines
1.1 KiB
NASM
69 lines
1.1 KiB
NASM
cpu 8086
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org 0x0000
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db 0x55, 0xAA
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db 0x00
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jmp near init
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times (0x18 - ($-$$)) db 0
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dw 0
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dw pnp
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pnp: 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 0 ; manufacturer string
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dw name ; 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 boot ; bootstrap entry point
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dw 0 ; reserved
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; zero for setting sreg without using reg
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zero: dw 0
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name: db "rdos", 0
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init: push ds
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; DS := 0
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mov ds, [cs:zero]
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; set entry points vectors
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mov word [0x19*4], boot
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mov word [0x19*4+2], cs
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pop ds
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retf
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; entry point on boot, preempting disks
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; this also doubles as entry point for reboot
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boot: xor ax, ax
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mov ss, ax
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mov sp, stack
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int 3
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hlt: hlt
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jmp hlt
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%include "kernel/intr.asm"
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align 512
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absolute 0x400
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resb (0x501 - ($-$$))
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; copy of the first 32 interrupt vectors
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ivt2: resd 0x20
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; 8kb stack
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alignb 2
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resw 0x2000
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stack:
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