37 lines
507 B
NASM
37 lines
507 B
NASM
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cpu 8086
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org 0x7C00
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jmp init
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%include "kernel/fd.asm"
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%include "kernel/con.asm"
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entry_int21: iret
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init: ; install int 21h handler
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mov ax, cs
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mov ds, ax
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mov es, ax
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mov word [4*0x21], entry_int21
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mov word [4*0x21+2], cs
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mov word [fd_table], con_ftab
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; print banner
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mov dx, .banner
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mov cx, 13
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mov bx, 0
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call con_write
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; execute shell
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mov ax, 0x4B00
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mov dx, .shellfn
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int 0x21
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.hlt: hlt
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jmp .hlt
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.banner: db "rdos kernel", 0x0A, 0x0D
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.shellfn: db "SHELL.COM", 0
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