X-Git-Url: http://git.mutantstargoat.com/user/nuclear/?a=blobdiff_plain;f=boot%2Fboot.asm;fp=boot%2Fboot.asm;h=0000000000000000000000000000000000000000;hb=426ed1c5006c82261fee2eea3feafe3282b2b862;hp=96506de177878426b08c7da880baebfe4cde1719;hpb=a7e2224fbb33e0662d6fd3fe21e91f5fe185fd4b;p=eightysix

diff --git a/boot/boot.asm b/boot/boot.asm
deleted file mode 100644
index 96506de..0000000
--- a/boot/boot.asm
+++ /dev/null
@@ -1,257 +0,0 @@
-; first stage boot loader
-	cpu 8086
-	bits 16
-	section .bootsect
-
-extern _stage2_start_seg
-extern _stage2_size
-
-boot_driveno	equ 7b00h
-num_read_tries	equ 7b06h	; 2 bytes
-sect_pending	equ 7b08h	; 2 bytes
-sect_per_track	equ 7b0ah	; 2 bytes
-cur_head	equ 7b0ch	; 2 bytes - current head
-start_sect	equ 7b0eh	; 2 bytes - start sector in track
-destptr		equ 7b10h	; 2 bytes - destination pointer
-num_heads	equ 7b12h	; 2 bytes - number of heads
-cur_cyl		equ 7b14h	; 2 bytes - current cylinder
-
-%macro floppy_motor_off 0
-	pushf
-	and dl, 80h
-	jnz %%end	; skip if high bit is set (i.e. it's not a floppy)
-	mov dx, 3f2h
-	in al, dx
-	and al, 0fh
-	out dx, al
-%%end:	popf
-%endmacro
-
-; 5.25" 360K floppy
-BPB_DISK_SECTORS	equ 720
-BPB_TRACK_SECTORS	equ 9
-BPB_MEDIA_TYPE		equ 0fdh
-; 3.5" 1.44M floppy
-;BPB_DISK_SECTORS	equ 2880
-;BPB_TRACK_SECTORS	equ 18
-;BPB_MEDIA_TYPE		equ 0f0h
-
-bios_param_block:
-	jmp start	; 2 bytes
-	nop		; 1 byte
-	; start of BPB at offset 3
-	db "86BOOT00"	; 03h: OEM ident, 8 bytes
-	dw 512		; 0bh: bytes per sector
-	db 1		; 0dh: sectors per cluster
-	dw 1		; 0eh: reserved sectors (including boot record)
-	db 2		; 10h: number of FATs
-	dw 224		; 11h: number of dir entries
-	dw BPB_DISK_SECTORS	; 13h: number of sectors in volume
-	db BPB_MEDIA_TYPE	; 15h: media descriptor type (f0 = 3.5" HD floppy)
-	dw 9		; 16h: number of sectors per FAT
-	dw BPB_TRACK_SECTORS	; 18h: number of sectors per track
-	dw 2		; 1ah: number of heads
-	dd 0		; 1ch: number of hidden sectors
-	dd 0		; 20h: high bits of sector count
-	db 0		; 24h: drive number
-	db 0		; 25h: winnt flags
-	db 28h		; 26h: signature(?)
-	dd 0		; 27h: volume serial number
-	db "80 SIX BOOT"; 2bh: volume label, 11 bytes
-	db "FAT12   "	; 36h: filesystem id, 8 bytes
-
-start:
-	cld
-	xor ax, ax
-	mov ds, ax
-	mov es, ax
-	jmp 00:.setcs
-.setcs:
-	; put the stack high
-	mov ax, 0x7f00
-	mov ss, ax
-	xor sp, sp
-	mov [boot_driveno], dl
-
-	; query sectors per track
-	mov ah, 8	; get drive parameters call, dl already has the drive
-	xor di, di
-	int 13h
-	jc .queryfail
-	and cx, 3fh
-	mov [sect_per_track], cx
-	mov cl, 8
-	shr dx, cl
-	inc dx
-	mov [num_heads], dx
-	jmp .querydone
-.queryfail:
-	; in case of failure, try 18 sectors per track, 2 heads
-	mov word [sect_per_track], 18
-	mov word [num_heads], 2
-.querydone:
-
-	; load the rest of the code high
-	mov ax, _stage2_size
-	add ax, 511
-	mov cl, 9
-	shr ax, cl
-	inc ax
-	mov [sect_pending], ax
-	mov ax, _stage2_start_seg
-	mov es, ax	; destination segment
-	mov word [destptr], 0
-	mov word [start_sect], 1	; start from sector 1 to skip boot sector
-	mov word [cur_cyl], 0
-	mov word [cur_head], 0
-
-.rdloop:
-	mov cx, [start_sect]
-	mov ax, [sect_pending]
-	sub ax, cx		; num_sect = pending - start_sect
-	cmp ax, [sect_per_track]
-	jbe .noadj
-	mov ax, [sect_per_track]	; read max sect_per_track at a time
-	sub ax, cx
-.noadj: test ax, ax
-	jz .done
-	push ax		; save how many sectors we're reading
-
-	push ax
-	push bx
-	push cx
-	push dx
-	push si
-	call print_hex_word
-	mov ax, str_rdtrack2
-	call printstr
-	mov ax, [cur_cyl]
-	call print_hex_byte
-	mov ax, str_rdtrack3
-	call printstr
-	mov ax, [cur_head]
-	call print_hex_byte
-	mov ax, str_rdtrack3
-	call printstr
-	mov ax, [start_sect]
-	call print_hex_byte
-	mov ax, str_newline
-	call printstr
-	pop si
-	pop dx
-	pop cx
-	pop bx
-	pop ax
-
-	mov ch, [cur_cyl]
-	mov dh, [cur_head]
-	mov bx, [destptr]
-
-	inc cl			; sector numbers start from 1
-	mov ah, 2		; read sectors is call 2
-	mov dl, [boot_driveno]
-	int 13h
-	jc .fail
-	; track read sucessfully
-	mov word [start_sect], 0	; all subsequent tracks are whole
-	mov ax, [cur_head]
-	inc ax
-	cmp ax, [num_heads]
-	jnz .skip_cyl_adv
-	xor ax, ax
-	inc byte [cur_cyl]
-.skip_cyl_adv:
-	mov [cur_head], ax
-
-	pop ax			; num_sect
-	sub [sect_pending], ax
-	push cx
-	mov cl, 9
-	shl ax, cl		; convert to bytes
-	pop cx
-	add [destptr], ax
-	jnz .rdloop
-
-	; loaded sucessfully, load segment registers and jump
-.done:	mov ax, _stage2_start_seg
-	mov ds, ax
-	mov es, ax
-	push ax
-	xor ax, ax
-	push ax
-	retf
-
-
-.fail:	add sp, 2	; clear num_sect off the stack
-	dec word [num_read_tries]
-	jz .abort
-
-	; reset controller and retry
-	xor ax, ax
-	mov dl, [boot_driveno]
-	int 13h
-	jmp .rdloop
-
-	; failed to load second sector
-.abort:	xor ax, ax
-	mov es, ax
-	floppy_motor_off	; turn off floppy motor (if dl is < 80h)
-	mov ax, str_load_fail
-	call printstr
-.hang:	hlt
-	jmp .hang
-
-	; expects string ptr in ax
-printstr:
-	mov si, ax
-.loop:	mov al, [si]
-	inc si
-	test al, al
-	jz .done
-	mov ah, 0eh
-	mov bx, 7
-	int 10h
-	jmp .loop
-.done:	ret
-
-print_hex_word:
-	mov cx, 4	; 4 digits to print
-	jmp print_n_hex_digits
-
-print_hex_byte:
-	mov cx, 2	; 2 digits to print
-	mov ah, al	; move them in place
-
-print_n_hex_digits:
-	rol ax, 1
-	rol ax, 1
-	rol ax, 1
-	rol ax, 1
-	mov dx, ax	; save ax, print_hex_digit destroys it
-	call print_hex_digit
-	mov ax, dx
-	dec cx
-	jnz print_n_hex_digits
-	ret
-
-print_hex_digit:
-	mov bl, al
-	and bx, 0fh
-	mov al, [bx + .hexdig_tab]
-	mov ah, 0eh
-	mov bx, 7
-	int 10h
-	ret
-
-.hexdig_tab:
-	db "0123456789abcdef"
-
-str_rdtrack2	db " from ",0
-str_rdtrack3	db "/",0
-str_load_fail	db "Failed to load 2nd stage!",0
-str_newline	db 13,10,0
-
-	times 510-($-$$) db 0
-bootsig dw 0xaa55
-
-; vi:set ts=8 sts=8 sw=8 ft=nasm: