moving a string to ax register

[xlav]

In main proc how do mov a string into the ax register? The string was defined as, message db "hello world","&" in the data segment.

 

[qbasicking]

It's been a while since I've used assembly but:

LEA ax, msg

ax is a 16 bit register, you can't place a string in it, just the memory address of the string. I believe that
MOV ax, [msg]
will work also.

 

[xlav]

Both examples give error 'undefined sybol: msg' when code is assembled.

-x

 

[xlav]

With MOV ax,[message] and LEA ax,message code assembles. When link get error-> 'fatal error LNK1190: invalid fixup found, type 0x0001'.

-x

 

[mseth]

Did you "initialize" your data segment?

 

[xlav]

The preceding code is,

.model small
.stack
.data
message db "Hello world","$"

.code

_main proc
LEA ax, msg
mov ds, ax

 

[mseth]

Well one thing is you have it declared as message and yet you are trying to do "LEA ax, msg" it doesn't know what's going on.

 

[xlav]

Replaced msg with message, code assembles. When link get error;

test2.obj : fatal error LNK1190: invalid fixup found, type 0x0001

 

[mseth]

You need to "initialize" the data segment, something like this:

http://employees.oneonta.edu/higgindm/asm1a.html

mov ax,data
mov ds,ax
mov dx,OFFSET message

 

[xlav]

Get error 'undefined symbol :data'.

CODE,

.model small
.stack
.data

message db "Assembly", "$"

.code

_main proc

mov ax,data
mov ds,ax
mov dx,OFFSET message
mov ah,09
lea dx,message
int 21h

mov ax,4c00h
int 21h
_main endp
end _main