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adefeo



Joined: 12 Jan 2004
Posts: 46
Location: Bellmore, Long Island, New York
adefeo
I've been working on my OS project, Metropolis (see http://512dev.us.tt for details once it's back up - changing webhosts now). It compiles right, but I can't get it to run. I don't get a PANIC or an error, but this is what the screen looks like:
Image
And the second underscore kinda flickers on and off O_o .

The source is at http://512net.juleos.co.uk/metro_dev/001source/
Bootloader is boot.asm
Kernel is kernel.asm (duh)
Command routines are in commands.inca
It's all realmode x86 ASM compiled with Win32 FASM 1.64

I make an image for bochs using this script:
Code:
fasm boot.asm boot.bin
fasm kernel.asm kernel.bin
copy /b boot.bin+kernel.bin osdisk.img
    

I then load osdisk.img into bochs with 8MB RAM, no hard drives, and 1 floppy drive...everything else is default values.

This is the bochsout.txt log:
Quote:

00000000000i[ ] Bochs x86 Emulator 2.2.1
00000000000i[ ] Build from CVS snapshot on July 8, 2005
00000000000i[ ] System configuration
00000000000i[ ] processors: 1
00000000000i[ ] A20 line support: yes
00000000000i[ ] APIC support: yes
00000000000i[ ] CPU configuration
00000000000i[ ] level: 6
00000000000i[ ] fpu support: yes
00000000000i[ ] paging support: yes, tlb enabled: yes
00000000000i[ ] mmx support: yes
00000000000i[ ] sse support: 1
00000000000i[ ] v8086 mode support: yes
00000000000i[ ] 3dnow! support: no
00000000000i[ ] PAE support: yes
00000000000i[ ] PGE support: yes
00000000000i[ ] PSE support: yes
00000000000i[ ] x86-64 support: no
00000000000i[ ] SEP support: no
00000000000i[ ] Optimization configuration
00000000000i[ ] Guest2HostTLB support: yes
00000000000i[ ] RepeatSpeedups support: yes
00000000000i[ ] Icache support: yes
00000000000i[ ] Host Asm support: yes
00000000000i[ ] Fast function calls: yes
00000000000i[MEM0 ] allocated memory at 00C40020. after alignment, vector=00C41000
00000000000i[MEM0 ] 8.00MB
00000000000i[MEM0 ] rom at 0xf0000/65536 ('../BIOS-bochs-latest')
00000000000i[MEM0 ] rom at 0xc0000/32768 ('../VGABIOS-lgpl-latest')
00000000000i[APIC?] local apic in initializing
00000000000i[APIC?] set APIC ID to 0
00000000000i[APIC0] 80686
00000000000i[APIC0] local apic in CPU apicid=00 initializing
00000000000i[IOAP ] initializing I/O APIC
00000000000i[IOAP ] set APIC ID to 1
00000000000i[CMOS ] Using local time for initial clock
00000000000i[CMOS ] Setting initial clock to: Sun Nov 27 17:06:59 2005 (time0=1133129219)
00000000000i[DMA ] channel 4 used by cascade
00000000000i[DMA ] channel 2 used by Floppy Drive
00000000000i[FDD ] fd0: 'osdisk.img' ro=0, h=2,t=80,spt=18
00000000000i[WGUI ] Number of Mouse Buttons = 3
00000000000i[WGUI ] IME disabled
00000000000i[CLVGA] VBE Bochs Display Extension Enabled
00000000000i[CLVGA] interval=300000
00000000000i[CLVGA] CL-GD5430 ISA initialized
00000000000i[ ] init_mem of 'harddrv' plugin device by virtual method
00000000000i[ ] init_mem of 'keyboard' plugin device by virtual method
00000000000i[ ] init_mem of 'serial' plugin device by virtual method
00000000000i[ ] init_mem of 'parallel' plugin device by virtual method
00000000000i[ ] init_mem of 'extfpuirq' plugin device by virtual method
00000000000i[ ] init_mem of 'gameport' plugin device by virtual method
00000000000i[ ] init_mem of 'speaker' plugin device by virtual method
00000000000i[ ] init_dev of 'harddrv' plugin device by virtual method
00000000000i[HD ] Using boot sequence floppy, none, none
00000000000i[HD ] Floppy boot signature check is enabled
00000000000i[ ] init_dev of 'keyboard' plugin device by virtual method
00000000000i[KBD ] will paste characters every 1000 keyboard ticks
00000000000i[ ] init_dev of 'serial' plugin device by virtual method
00000000000i[SER ] com1 at 0x03f8 irq 4
00000000000i[ ] init_dev of 'parallel' plugin device by virtual method
00000000000i[PAR ] parallel port 1 at 0x0378 irq 7
00000000000i[ ] init_dev of 'extfpuirq' plugin device by virtual method
00000000000i[ ] init_dev of 'gameport' plugin device by virtual method
00000000000i[ ] init_dev of 'speaker' plugin device by virtual method
00000000000i[ ] reset of 'harddrv' plugin device by virtual method
00000000000i[ ] reset of 'keyboard' plugin device by virtual method
00000000000i[ ] reset of 'serial' plugin device by virtual method
00000000000i[ ] reset of 'parallel' plugin device by virtual method
00000000000i[ ] reset of 'extfpuirq' plugin device by virtual method
00000000000i[ ] reset of 'gameport' plugin device by virtual method
00000000000i[ ] reset of 'speaker' plugin device by virtual method
00000004447i[BIOS ] rombios.c,v 1.138.2.1 2005/07/06 19:30:36 vruppert Exp $
00000318004i[KBD ] reset-disable command received
00000420033i[VBIOS] VGABios $Id: vgabios.c,v 1.62 2005/07/02 18:39:43 vruppert Exp $

00000420104i[CLVGA] VBE known Display Interface b0c0
00000420136i[CLVGA] VBE known Display Interface b0c3
00000423061i[VBIOS] VBE Bios $Id: vbe.c,v 1.47 2005/05/24 16:50:50 vruppert Exp $
00000450000i[WGUI ] dimension update x=720 y=400 fontheight=16 fontwidth=9 bpp=8
00000825000i[WGUI ] dimension update x=360 y=400 fontheight=16 fontwidth=9 bpp=8
00421251750p[WGUI ] >>PANIC<< Window closed, exiting!
00421251750i[SYS ] Last time is 1133130904
00421251750i[CPU0 ] real mode
00421251750i[CPU0 ] CS.d_b = 16 bit
00421251750i[CPU0 ] SS.d_b = 16 bit
00421251750i[CPU0 ] | EAX=0fff0030 EBX=00000050 ECX=00110000 EDX=00000014
00421251750i[CPU0 ] | ESP=00006262 EBP=00000000 ESI=00000030 EDI=00000119
00421251750i[CPU0 ] | IOPL=0 NV UP DI PL ZR NA PE NC
00421251750i[CPU0 ] | SEG selector base limit G D
00421251750i[CPU0 ] | SEG sltr(index|ti|rpl) base limit G D
00421251750i[CPU0 ] | CS:2700( 0000| 0| 0) 00027000 0000ffff 0 0
00421251750i[CPU0 ] | DS:0000( 0000| 0| 0) 00000000 0000ffff 0 0
00421251750i[CPU0 ] | SS:0000( 0000| 0| 0) 00000000 0000ffff 0 0
00421251750i[CPU0 ] | ES:2700( 0000| 0| 0) 00027000 0000ffff 0 0
00421251750i[CPU0 ] | FS:0000( 0000| 0| 0) 00000000 0000ffff 0 0
00421251750i[CPU0 ] | GS:0000( 0000| 0| 0) 00000000 0000ffff 0 0
00421251750i[CPU0 ] | EIP=00000048 (00000048)
00421251750i[CPU0 ] | CR0=0x00000010 CR1=0 CR2=0x00000000
00421251750i[CPU0 ] | CR3=0x00000000 CR4=0x00000000
00421251750i[ ] restoring default signal behavior
00421251750i[CTRL ] quit_sim called with exit code 1


Any help to why this is failing to run correctly would be GREATLY appreciated.

Thanks,
Anthony
Post 27 Nov 2005, 22:15
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Octavio



Joined: 21 Jun 2003
Posts: 366
Location: Spain
Octavio
first replace ' org 7c0h ' by 'org 7c00h'
second make that your code prints messages to know what is happening.
and donĀ“t try to do a lot of things with the boot sector, just load the kernel
or a second stage loader in real mode.
and also read other OS sources to learn.
Post 28 Nov 2005, 14:31
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Artlav



Joined: 23 Dec 2004
Posts: 188
Location: Moscow, Russia
Artlav
Wow... Runned it through the debugger. Result: 13 bugs.
Here is the correct code, corrections marked with ;###

In the boot.asm put 7c00 instead of 7c0 (typo?).

Also i reccomend this function, if you using the Bochs emulator, it prints the debug in the bochs console:

Code:
print2e9: ;ds:si 0-string addres
nop
push    ax si

lp2e9:
lodsb
cmp     al,0
je      endpr2e9
out     0e9h,al
jmp     lp2e9

endpr2e9:
pop     si ax
ret
;###endp        print2e9
    


kernel.asm:
Code:
use16
org 0x0000
command_length equ 3   ;###Constants better be before all (to be available for all)

jmp     begin           ;### Otherwise the cls code will be executed before setup

include 'commands.inc'

;====================
;Main kernel program
;====================

begin:
;reset segment registers
mov ax, cs
mov ds, ax
mov es, ax

main:
mov si, welcomemsg
call kprint
jmp loadprompt

;====================
;Kernel routines
;====================
kprint:         ;string output, SI = string
mov ah,0x0E
mov bh,0x00
mov bl,0x15
nextchar:
lodsb
or al,al
jz return
int 0x10
jmp nextchar
return:
ret

kputchar:       ;char output, al = char code ;##Absent from the original
mov ah,0x0E
mov bh,0x00
mov bl,0x15
int 0x10
ret

kscanf:         ;string input, DX = max length, if CX != 0, then string isnt echoed
xor bx, bx
start:

xor ax, ax
int 0x16        ;##Input with wait - int 16h, AX=0000h
cmp al, 0x0D
je return_press
mov [es:di+bx], al
inc bx
cmp bx, dx
je return_press
push bx
xor bx,bx
cmp bx,cx
je putchar

putreturn:
pop bx          ;##Stack async - multiple problems, when amount of push not equals amount of pop's
jmp start

putchar:
pop bx
push bx         ;##Stack async (2)
xor ah,ah

call kputchar   ;##Originally it calls the putchar label above, while there was no putchar function
jmp putreturn

return_press:
xor al,al
mov [es:di+bx],al
ret

loadprompt:     ;display the command prompt
mov si, loadpromptmsg   ;##Was loadprompt - loaded the addres of loadprompt ael instead of msg (typo?)
call kprint
mov si, prompt_title
call kprint
commandready:
mov si, prompt
call kprint
xor cx, cx
mov dx, 20

mov di, cmdbuffer
call kscanf


;routines to compare inputs to builtin commands
;will also compare to disk files once FAT12 support is implemented

compare_command_cls:    ;##locating the variable after the labeb makes the transfer in the label, instead of the code.
mov di, cmdbuffer
mov si, command_cls
mov cx, command_length
repe cmpsb              ;##cmpsw compares words, while yoou got bytes
                        ;##cmp cx,0 is useless, since rep cmpsb returns zf flag.
je cls
jmp invalid_cmd

invalid_cmd:
mov si, invalidcmd
call kprint
jmp commandready


;====================
;Data
;====================

welcomemsg db 'Metropolis 0.01 Codename Infinity: Kernel Loaded',13,10,0
loadpromptmsg db 'Starting shell...',13,10,0
prompt_title db 'MetroShell 0.1',13,10,0
command_cls db "cls",0  ;##Movedthe command there - better location
invalidcmd db 'The command entered was not recognized',13,10,0
prompt db '>',0
cmdbuffer db 0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0

times 1024-$ db 0
    
Post 28 Nov 2005, 17:41
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Rohan



Joined: 14 Jul 2005
Posts: 13
Rohan
can you help me with my bootsector it doesn't work
Code:


        use16

        org 0x7C00
        jmp start

;-------------------------------------
OSName          db  'noname'  ;
BytsPerSec       dw   512       ;
ReservedSec       dw   1         ;
SecPerFAT          db   2         ; 
SecPerClus          db   1         ;
TotalSect            dw   2880      ;
RootEntriesSize       dw   511       ;
MediaType              db   0xf0      ;
FatSize                dw   9         ;
TrackSect             dw   18        ;
Heads                dw  2          ;
FATCopy             db   1         ;
SecPerPartit       db   2         ;
HidenSec          dd   0         ; ?-4
SecPerTrack      db   2         ;
LargeSec        dd   0         ;
;--------------------------------------
Reserved        db      0     ;
Signatured      db      0     ;
FddNumber       db   1        ;
FSType          db   'FAT12'  ;


start:

                mov cx,3
read:

      _loop:    mov ah,0         ; 
                int 13h
                mov ah,2         ; 
                int 13h
                xor cx,cx        ; 
                xor dl,dl        ; ffd A
                mov dh,1         ; 
                mov cl,4         ; 
                int 13h
                je  ok           ; 
                dec cx
                jz error         ; 
                jmp read

ok:
        mov al,3
        mov bh,0
        mov cx,8
        mov dh,12
        mov dl,45
        mov bp,Name
        int 13h

error:
        mov al,3
        mov bh,0
        mov cx,12
        mov bp,ermsg
        int 13h



ermsg db 'Error$'
Name   db 'Test'

int 20h
rb 7C00h+512-2-$
dw 0xAA55

    
Post 01 Jan 2006, 18:42
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