CODEWITHSUNDEEP
assemblydosx86-16tasm
Аня Сан
Аня Сан

Reputation: 13

Why am I getting these errors in my assembly code (Option casemap: none)?

I'm writing assembly code with the GUI Turbo Assembler (a Turbo Assembler GUI environment for Windows that produces DOS programs that run in DOSBox). When I run the program the assembler gives this error:

x.asm Error x.asm(3) Illegal instruction

Line 3 is option casemap: none. My code is:

.586                                  
.model flat,stdcall ;           
option casemap:none ; Line that is giving an error             
.DATA               ;              
x db 2             ;           
y db 1          
z db 1        
 .data?           
 a db ?       ;           
 b db ?       ; b=2             
 c db ?       ; c=2              
 d db ?       ; d=2                  
 e db ?       ; e=23,5               
 f db ?       ; f=4                   
 g db ?       ; g=-18,5                              
 .code       ;                                                    
 beg:        ;                                                

 mov  ah,x  ; AH:=x                 
 mov  bh,z  ; BH:=z                        
 imul bh    ; AH:=xz:=2                  
mov  b,ah  ; b:=2                          

mov  ah,x   ; AH:=x                      
mov  ch,y   ; CH:=y                   
idiv ch    ; AH:=AH/CH:=x/y:=2                  
mov  ch,ah ; CH:=2                 
mov  c,ch  ; c=2          

mov  ah,y   ; AH:=y                      
mul  ah     ; AH=1^2=1                     
mov  bh,z  ; BH:=z                    
imul bh    ; AH:=yz:=1                 
mov  ch,x  ;  CH=x                  
imul ch    ; AH=AHCH=1x=2                              
mov  d,ah ; d=2                                      

mov AH,45 ; AH=45                      
mov BH, d ; BH=2               
idiv BH   ; AH=45/2=22,5                  
mov e, AH ; e=22,5              

mov ah,b  ; AH=b                            
mov ch,c  ; CH=c                 
add ah,ch; AH=b+c=2+2=4               
mov f, ah; AH=f               

mov ah,f  ; AH=f                   
mov ch, e ; CH=e                    
sub ah,ch; AH=4-22,5=-18,5                   
mov g,ah  ; g=-18,5             

mov ah,g  ; AH=g             
mov ch,5  ; CH=5                 
sub ah,ch; AH=-18,5-5=-23,5               

mov a,ah  ; a=AH=-23,5                                     

end beg

Upvotes: 1

Views: 1190

Answers (1)

Michael Petch
Michael Petch

Reputation: 47573

The OPTION keyword wasn't introduced until TASM 5 according to the change logs. GUI Turbo Assembler currently uses TASM 4.1. You don't need the OPTION CASEMAP feature since your code uses all the same case for the labels in your code. The fix is to remove:

option casemap:none

Since GUI Turbo Assembler targets running DOS programs you will need to change:

.model flat,stdcall

to something like:

.model small,stdcall

In DOS the memory models can be small. medium, compact, large, and huge . flat doesn't apply to DOS programs. Using flat will result in a linker error under the GUI Turbo Assembler environment.

For DOS you will also want to add a stack and specify its size. Something like this should work:

.stack 256          ; Set stack size to 256 bytes

Upvotes: 3

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