Why doesn't this code write all lines?

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joachim_neu

Joined: 22 Dec 2003
Posts: 139

joachim_neu 08 Mar 2004, 08:14

hello,

I've got a new problem... I coded a code, which should read 512 chars from the monitor and then it should write it to the drive... My problem is, that the code doesn't write the first and the last line... It is such a unlogical problem and I don't know the answer... Please help me, this is the part of my code:

Code:

; Schreibt einen Sektor auf die Platte
wrs:
call sdel
mov si,wr_choice
call putstr
call getkey
cmp ah,1Fh
jz wr_sc
cmp ah,1Eh
jz wr_as
wr_sc:
mov si,sc_choice
call putstr
mov ax,0x5000
mov es,ax
mov ax,0h
mov di,ax
mov cx,200h
sc_schl:
call writekey
cmp ah,01h
jz writes
mov al,ah
stosb
loop sc_schl
jmp writes
wr_as:
mov si,as_choice
call putstr
mov ax,0x5000
mov es,ax
mov ax,0h
mov di,ax
mov cx,200h
as_schl:
call writekey
cmp ah,01h
jz writes
stosb
loop as_schl
jmp writes                 
.......
writes:
mov si,write_msg
call putstr
mov ch,00h
mov dx,0000h
mov bx,0h
mov ax,0x5000
mov es,ax
call getkey
dec ah
mov cl,ah
mov ah,03h
mov al,01h
int 13h
jmp START    



; Stringausgabe
putstr:
lodsb            ; Byte laden
or al,al
jz short putstrd ; 0-Byte? -> Ende!
mov ah,0x0E      ; Funktion 0x0E
mov bx,0x0007    ; Atrribut-Byte
int 0x10         ; schreiben
jmp putstr       ; nÃ¤chstes Byte
putstrd:
retn

; Warte auf einen Tastendruck
getkey:
mov ah, 0 ; Funktion 0
int 016h  ; AusfÃ¼hren
ret

; Wartet auf einen Druck und zeigt ihn an
writekey:
mov ah, 0 ; Funktion 0
int 016h  ; AusfÃ¼hren
mov dx,ax
mov bl,07h
mov ah,0Eh
int 10h
mov ax,dx
ret

;lÃ¶scht einen Speichersektor
sdel:
mov ax,0x5000
mov es,ax
mov ax,0h
mov di,ax
mov cx,200h
delschl:
xor ax,ax
stosb
loop delschl
ret

Please help me!!!!!!!!!!!

JOACHIM NEU

08 Mar 2004, 08:14

JohnFound

Joined: 16 Jun 2003
Posts: 3499
Location: Bulgaria

JohnFound 08 Mar 2004, 09:02

Hi.
What you tryed to solve the problem?

Regards

08 Mar 2004, 09:02

joachim_neu

Joined: 22 Dec 2003
Posts: 139

joachim_neu 08 Mar 2004, 09:50

sorry, I didn't try anything special, because I didn't saw the logic behind it, I think, there's something wrong, because normally a computer writes all or nothing but something in the middle wasn't logically for me, so I couldn't do something...

08 Mar 2004, 09:50

joachim_neu

Joined: 22 Dec 2003
Posts: 139

joachim_neu 08 Mar 2004, 09:52

If it whould only not write the last 20 chars, I whould see a logic, but exactly allways the first and the last line... Sometimes the last line are 30 or 32 chars and so there I found no logic...

08 Mar 2004, 09:52

joachim_neu

Joined: 22 Dec 2003
Posts: 139

joachim_neu 08 Mar 2004, 10:45

,

I did a mistake... The mistake is not in the write-code (I tested with bootread from bitdog, I wrote in sector 1 and read it with bootread), the mistake is in the read-code, but where?:

Code:

; LieÃŸt Sektoren von der Platte
loads:
mov si,load_msg
call putstr

; Diskdrive reset (Interrupt 13h, 0)
push ds            ; Save DS
mov ax, 0          ; The function (reset)
mov dl, 0          ; This drive
int 13h            ; run the interrupt
pop ds             ; DS recover
jc loads            ; Misstake? Again!

load1:
mov ax,0x5000      ; ES:BX = 50000
mov es,ax
mov bx, 0

; read sectors (Interrupt 13h, 2)
mov ch,00h
call getkey
dec ah
mov cl,ah
mov dx,0x0000
mov al,1h
mov ah,2h       ; Function 2 (Lesen)
int 13h         ; ES:BX =  Dates of the drive
jc load1        ; misstake? again!

mov ax,0x5000
mov es,ax
mov BP, 0
mov AH,13h
mov AL,0h
mov BL,07h
mov BH,00h
mov CX,0x200
mov DH,19h
mov DL,0
int 10h

mov si,empty
call putstr
jmp START

thanks

JOACHIM NEU

08 Mar 2004, 10:45

JohnFound

Joined: 16 Jun 2003
Posts: 3499
Location: Bulgaria

JohnFound 08 Mar 2004, 10:59

Good. You have an advance.
Keep working this way.

regards.

08 Mar 2004, 10:59

joachim_neu

Joined: 22 Dec 2003
Posts: 139

joachim_neu 08 Mar 2004, 11:37

I think some empty lines are written over the others...

I'll test it...

08 Mar 2004, 11:37

joachim_neu

Joined: 22 Dec 2003
Posts: 139

joachim_neu 08 Mar 2004, 18:48

thanks... there were two lines overlapped, the last were empty....

08 Mar 2004, 18:48

JohnFound

Joined: 16 Jun 2003
Posts: 3499
Location: Bulgaria

JohnFound 08 Mar 2004, 18:54

Great!

08 Mar 2004, 18:54

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