Show Registers (16-bit)

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Picnic

Joined: 05 May 2007
Posts: 1389
Location: Piraeus, Greece

Picnic 24 May 2007, 20:29

A simple script i wrote in fasm to display CPU registers in Debug style.

Code:

ORG 100H
CALL SHOWR
INT 20H

SHOWR:
PUSH AX BX CX DX SI DI ES BP
PUSH SP SS ES DS CS BP SI DI DX CX BX AX
MOV SI,REGSTR
MOV CX,12
@@:
MOV DL,BYTE [SI]
CALL PUTC
MOV DL,BYTE [SI+1]
CALL PUTC
MOV DL,BYTE [SI+2]
CALL PUTC
ADD SI,3
POP AX
CALL HEXWORD
MOV DL, ' '
CALL PUTC
LOOP @B
POP BP ES DI SI DX CX BX AX
CALL NEWLINE
RET

HEXWORD:
PUSH AX
MOV AL,AH
CALL HEXBYTE
POP AX
CALL HEXBYTE
RET

HEXBYTE:
PUSH AX
ROL AL,4
CALL DIGIT
POP AX
CALL DIGIT
RET

DIGIT:
PUSH AX DX
AND AL,0FH
ADD AL,30H
CMP AL,'9' + 1
JC @F
ADD AL,7
@@:
MOV DL,AL
CALL PUTC
POP DX AX
RET
        
PUTC:
PUSH AX
MOV AH,02H
INT 21H
POP AX
RET

NEWLINE:
PUSH AX DX
MOV AH,02H
MOV DL,0AH
INT 21H
MOV DL,0DH
INT 21H
POP DX AX
RET

REGSTR DB 'AX=BX=CX=DX=DI=SI=BP=CS=DS=ES=SS=SP='

Last edited by Picnic on 21 Mar 2020, 10:24; edited 2 times in total

24 May 2007, 20:29

jatos

Joined: 04 Nov 2006
Posts: 20

jatos 31 May 2007, 21:50

Thanks for that. This program is something I really wanted!

_________________
Jamie

31 May 2007, 21:50

Picnic

Joined: 05 May 2007
Posts: 1389
Location: Piraeus, Greece

Picnic 11 Jun 2007, 19:50

Be well jatos!

Here is another script i wrote in fasm. It displays memory contents.
It's my first attempt to use a macro.

Code:

MACRO PUTC [ARG] {
 LOCAL EXIT
 IF ARG EQTYPE '' | ARG EQTYPE 0
  MOV DL,ARG
 ELSE
  CMP DL,20H
  JAE EXIT
  MOV DL,'.'
  END IF
  EXIT:
  MOV AH,2
  INT 21H
 }
 
MACRO INIT REGAX,REGSI,REGDI {
 MOV AX,REGAX
 MOV SI,REGSI
 MOV DI,REGDI
 MOV ES,AX
 MOV BX,TABLE
 }
 

ORG 100H
INIT 1234H,100H,200H   ;SEGMENT ADDRESS,STARTING ADDRESS,ENDING ADDRESS
CALL DUMP
RET

DUMP:
PUTC 13,10
MOV DX,ES
CALL HEXWORD
PUTC ':'
MOV DX,SI
CALL HEXWORD
PUTC ' '
MOV CX,16
PUSH SI
@@:
MOV DL,[ES:SI]
INC SI
CALL HEXBYTE
PUTC ' '
LOOP @B
POP SI
MOV CX,16
PUTC ' '
@@:
MOV DL,[ES:SI]
INC SI
PUTC DL
LOOP @B
CMP SI,DI
JL DUMP
RET
        
HEXWORD:
XCHG DH,DL
CALL HEXBYTE
XCHG DH,DL
CALL HEXBYTE
RET

HEXBYTE:
MOV AL,DL
SHR AL,4
XLATB        
MOV AH,0EH 
INT 10H
MOV AL,DL
AND AL,0FH 
XLATB            
MOV AH,0EH
INT 10H
RET

TABLE DB '0123456789ABCDEF'

11 Jun 2007, 19:50

m

Joined: 28 Dec 2006
Posts: 304
Location: in

m 30 Jun 2007, 10:57

Cooool eh!

30 Jun 2007, 10:57

rugxulo

Joined: 09 Aug 2005
Posts: 2341
Location: Usono (aka, USA)

rugxulo 01 Jul 2007, 21:54

Code:

; use FASMD and press F9 to assemble / run, then Alt+F5 to see screen
;
; EDIT: fixed to be 8086 compatible
;
; 30 bytes (could it be smaller??)

org 100h

mov ax,0BEEFh
call hexword
ret

hexword:
          mov cx,4
.begin:
          push cx
          mov cl,4
          rol ax,cl
          pop cx
          push ax
          and al,0Fh
          cmp al,10
          sbb al,69h
          das
          int 29h
          pop ax
          loop .begin
.ret:
          ret

01 Jul 2007, 21:54

Picnic

Joined: 05 May 2007
Posts: 1389
Location: Piraeus, Greece

Picnic 10 Jan 2008, 20:08

Again the 16-bit registers for anyone interested.

Code:

; Display 16-bit registers

showr:
  pusha
       pushf
       push sp ss es ds cs bp si di dx cx bx ax
    mov si,regstr
       mov cl,12
.reg:
      lodsb
       int 29h
     lodsb
       int 29h
     lodsb
       int 29h
     mov ch,4
    pop ax                                 ; ax bx cx dx ..
.digit:
         rol ax,4
         push ax
         and al,0fh
         cmp al,10
         sbb al,69h
         das
         int 29h    
         pop ax
         dec ch
         jnz .digit
         mov al,' '
   int 29h        
     loop .reg
   mov al,13
   int 29h
     mov al,10
   int 29h
     popf
        popa
        ret
         
    
         regstr db 'AX=BX=CX=DX=DI=SI=BP=CS=DS=ES=SS=SP='

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Hobby BASIC Interpreter

10 Jan 2008, 20:08

edfed

Joined: 20 Feb 2006
Posts: 4330
Location: Now

edfed 12 Jan 2008, 01:36

good, thimis, good good good! Very Happy

and for somebody interrested for non dos dependance:

Description:	need some modifications if you need. easily bootable	Download
Filename:	whatsegment.zip
Filesize:	972 Bytes
Downloaded:	746 Time(s)

_________________
Smile

fool gitlab fasmstuff
gitlab foolstuff

12 Jan 2008, 01:36

Picnic

Joined: 05 May 2007
Posts: 1389
Location: Piraeus, Greece

Picnic 13 Jan 2008, 13:08

Thank you edfed.
P.S I used code from rugxulo's post above as it appears.

13 Jan 2008, 13:08

Slai

Joined: 11 Jan 2006
Posts: 40
Location: NY/Bulgaria

Slai 22 Jan 2008, 20:21

rugxulo I do not get why do you use
push cx
mov cl,4
rol ax,cl
pop cx
instead of just "rol ax, 4", but you can save few bites this way.

22 Jan 2008, 20:21

Slai

Joined: 11 Jan 2006
Posts: 40
Location: NY/Bulgaria

Slai 22 Jan 2008, 20:28

rugxulo your code helped me to improve my ShowHex macro with the push/pop ax, thanks! And I learned from you about the int 29h, does that work on all PCs ?

22 Jan 2008, 20:28

LocoDelAssembly
Your code has a bug

Joined: 06 May 2005
Posts: 4624
Location: Argentina

LocoDelAssembly 22 Jan 2008, 20:51

Quote:

instead of just "rol ax, 4", but you can save few bites this way.

Because "rol reg, imm8" is not available in 8086 (except for "rol reg, 1").

22 Jan 2008, 20:51

DOS386

Joined: 08 Dec 2006
Posts: 1900

DOS386 23 Jan 2008, 01:31

> Because "rol reg, imm8" is not available in 8086 (except for "rol reg, 1").

Code:

push cx
mov cl,4
rol ax,cl
pop cx

Great ^^^ code, if you need obfuscation or save 2 bytes Laughing

Code:

  rol ax,1 ; This eats 2 BYTES !!!
  rol ax,1
  rol ax,1
  rol ax,1

Would be the "bloated" 8086-compatible solution Idea

_________________
Bug Nr.: 12345

Title: Hello World program compiles to 100 KB !!!

Status: Closed: NOT a Bug

23 Jan 2008, 01:31

edfed

Joined: 20 Feb 2006
Posts: 4330
Location: Now

edfed 23 Jan 2008, 23:38

Code:

 
push cx si 
mov si,roller
mov cl,[si] 
rol ax,cl 
pop si cx

can be modular too. use more bytes, but for memory programable rol, it's good.

23 Jan 2008, 23:38

LocoDelAssembly
Your code has a bug

Joined: 06 May 2005
Posts: 4624
Location: Argentina

LocoDelAssembly 23 Jan 2008, 23:47

And what was the problem with

Code:

push cx  
mov cl, [roller]  
rol ax, cl  
pop cx

23 Jan 2008, 23:47

rugxulo

Joined: 09 Aug 2005
Posts: 2341
Location: Usono (aka, USA)

rugxulo 25 Jan 2008, 03:48

First of all, sorry, thimis, about silently updating the code without PM'ing you or something. Yeah, when I initially posted the code using rol ax,4, I forgot about 8086-compatible code, which doesn't really waste much of anything and runs everywhere. So I personally prefer compatibility in such a case.

25 Jan 2008, 03:48

edfed

Joined: 20 Feb 2006
Posts: 4330
Location: Now

edfed 25 Jan 2008, 04:26

the problem was that si can be defined before, and the last 3 instructions used in a loop.

Code:


         push si
         mov si,[roller]
;assume esi never changed for all but the index of roller
...
         push cx
         mov cl,[si]
         rol ax,cl
         pop cx
...
         inc si
         push cx
         mov cl,[si]
         rol ax,cl
         pop cx
         pop si
...
roller db 5,4,3,2,1,4,3,4,3,4,0

25 Jan 2008, 04:26

Picnic

Joined: 05 May 2007
Posts: 1389
Location: Piraeus, Greece

Picnic 25 Jan 2008, 20:23

rugxulo wrote:

First of all, sorry, thimis, about silently updating the code without PM'ing you or something.

No problem rugxulo, i was aware about this compatibility issue.

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25 Jan 2008, 20:23

LocoDelAssembly
Your code has a bug

Joined: 06 May 2005
Posts: 4624
Location: Argentina

LocoDelAssembly 18 May 2009, 22:04

For the Windows version see http://board.flatassembler.net/topic.php?t=10183

18 May 2009, 22:04

bitshifter

Joined: 04 Dec 2007
Posts: 796
Location: Massachusetts, USA

bitshifter 02 Nov 2012, 09:36

rugxulo wrote:

Code:

; use FASMD and press F9 to assemble / run, then Alt+F5 to see screen
;
; EDIT: fixed to be 8086 compatible
;
; 30 bytes (could it be smaller??)

org 100h

mov ax,0BEEFh
call hexword
ret

hexword:
          mov cx,4
.begin:
          push cx
          mov cl,4
          rol ax,cl
          pop cx
          push ax
          and al,0Fh
          cmp al,10
          sbb al,69h
          das
          int 29h
          pop ax
          loop .begin
.ret:
          ret

Sorry to revive an old (but interesting) thread.
Anyway, yes it can be smaller, by 2 bytes (28 vs 30)...

Code:


org 0x0100
use16

main:
 mov dx,0xBEEF
 call hexword
;mov ah,0x08
;int 0x21
 ret

hexword:
 mov cx,0x0404
.again:
 rol dx,cl
 mov al,dl
 and al,0x0F
 cmp al,0x0A
 sbb al,0x69
 das
 int 0x29
 dec ch
 jnz .again
 ret

Uncomment the two lines if you need to pause in console...

_________________
Coding a 3D game engine with fasm is like trying to eat an elephant,
you just have to keep focused and take it one 'byte' at a time.

02 Nov 2012, 09:36

ght2142

Joined: 11 Oct 2012
Posts: 3

ght2142 03 Nov 2012, 09:53

I must say Picnic, I am impressed. Very Happy

03 Nov 2012, 09:53

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