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|
bits 16
jmp kmain
%include "constants.asm"
%include "string.asm"
%include "disk.asm"
%include "console.asm"
%include "stdio.asm"
kmain:
cli ; disable interrupts
mov ax, cs ; get code segment
mov ds, ax ; set data segment
mov es, ax ; set extra segment
mov ax, 8000h
mov ss, ax ; set stack segment
mov sp, 0ffffh ; set stack pointer (~64k)
sti ; enable interrupts
mov [drive0], dx ; store bootloader's drive number
; reset general purpose registers
xor ax, ax
xor bx, bx
xor cx, cx
xor dx, dx
xor di, di
xor si, si
xor bp, bp
call cls ; clear console
push 0 ; home the cursor
call setcursor
push msg_entry_point
call puts
add sp, 2
push cs
call printh
mov al, ':'
call putc
mov ax, kmain
push ax
call printh
add sp, 4
mov al, CR
call putc
;--- stack
push msg_entry_point_stack
call puts
add sp, 2
push ss
call printh
mov al, ':'
call putc
push sp
call printh
add sp, 4
mov al, CR
call putc
push banner
call puts
add sp, 2
.mainloop:
call kbd_read
call putc
jmp .mainloop
cli
jmp $
panic:
; Hang system with supplied error message
push bp
mov bp, sp
push error_msg_panic ; i.e. 'PANIC:'
call puts
add sp, 2
push word [bp + 4] ; address of error string buffer
call puts ; print error
add sp, 2
cli ; disable interrupts
jmp $ ; hang (no return)
; stack is dead
; data
msg_entry_point: db 'Loaded at ', 0
msg_entry_point_stack: db 'Stack at ', 0
banner: db "+========================+", CR
db "| Welcome to MINOS 0.0.1 |", CR
db "+========================+", CR
db CR, 0
; Error messages
error_msg_panic: db "PANIC: ", 0
times 512 * 20h db 0
dw 0xefbe
|
