SliTaz Repositories

     1.1 --- a/tfttest/stuff/bootloader.S	Sat May 08 17:23:19 2021 +0000
     1.2 +++ b/tfttest/stuff/bootloader.S	Wed Jul 14 09:04:04 2021 +0000
     1.3 @@ -5,40 +5,57 @@
     1.4  	.globl	_start
     1.5  _start:
     1.6  	call	start2
     1.7 +	
     1.8 +BPB	=	0x3E
     1.9 +#define TINY_MENU	Tiny SliTaz floppy boot menu
    1.10 +#ifdef	TINY_MENU
    1.11 +	.org	BPB-12
    1.12 +	xchgw	%ax, %di		# 79 58 41 E8
    1.13 +	popw	%ax
    1.14 +	incw	%cx
    1.15 +	call	called
    1.16 +called:
    1.17 +	addw	$0x20, %cs:bootseg+0x201	# code at 07C0:0200
    1.18 +	.org	BPB, 0x90
    1.19 +#endif
    1.20 +	
    1.21 +	.org	BPB
    1.22  start2:
    1.23 -	popw	%bx
    1.24 -	cmpb	$0x1, %bh
    1.25 +	popw	%ax
    1.26 +com_offset	=	0x100
    1.27 +	cmpw	$com_offset+3, %ax
    1.28  	je	dotcom
    1.29 -	xorw	%ax, %ax		# %ax = 0
    1.30 -	movw	%ax, %ds
    1.31 -	leaw	int21-start2(%bx), %ax
    1.32 -	movw	%ax,0x21*4
    1.33 -	movw	%cs,0x21*4+2
    1.34 -	movw	$0x7C0-0x10, %ax
    1.35 -	movw	%ax, %ds
    1.36 +	cwd
    1.37 +int21hook:
    1.38 +	movb	$int21-_start, %al
    1.39 +	movw	%dx, %ds
    1.40 +	movw	%ax, 0x21*4
    1.41 +	movw	%cs, 0x21*4+2
    1.42 +bootseg:
    1.43 +	movw	$0x7C0-com_offset/16, %ax
    1.44 +	.byte	0x3d			# cmp $0xc88c, %ax
    1.45  dotcom:
    1.46 -	movw	%ds, %ax
    1.47 -	addw	$6, %ax			# addw $code/16, %ax
    1.48 +	movw	%cs, %ax
    1.49 +paragraphs	=	9
    1.50 +	addw	$paragraphs, %ax
    1.51  	movw	%ax, %ds
    1.52  	movw	%ax, %es
    1.53  	movw	%ax, %ss
    1.54  	movw	$0xFFFE, %sp
    1.55 -	pushw	%ds
    1.56 -	movw	$0x100, %ax
    1.57  	pushw	%ax
    1.58 -	cbw
    1.59 -	xorw	%bx, %bx
    1.60 +	movw	$com_offset, %ax
    1.61 +	pushw	%ax
    1.62 +	cbw				# %ax = 0
    1.63  	retf
    1.64  
    1.65  int21:
    1.66 -	cmpb	$7, %ah
    1.67 +	subb	$7, %ah
    1.68  	jne	not_input
    1.69 -	movb	$0, %ah
    1.70 -	int	$0x16
    1.71 +	int	$0x16			# %ah = 0
    1.72  do_iret:
    1.73  	iret
    1.74  not_input:
    1.75 -	cmpb	$9, %ah
    1.76 +	cmpb	$9-7, %ah
    1.77  	jne	abort
    1.78  	movw	%dx, %si
    1.79  puts:
    1.80 @@ -51,8 +68,8 @@
    1.81  	jmp	puts
    1.82  abort:
    1.83  	ljmp	$0xffff,$0
    1.84 -	
    1.85 -	.org	0x60
    1.86 +
    1.87 +	.org	paragraphs*16	
    1.88  code:
    1.89  	.org	510	
    1.90