×
INTELLIGENT WORK FORUMS
FOR COMPUTER PROFESSIONALS

Contact US

Log In

Come Join Us!

Are you a
Computer / IT professional?
Join Tek-Tips Forums!
  • Talk With Other Members
  • Be Notified Of Responses
    To Your Posts
  • Keyword Search
  • One-Click Access To Your
    Favorite Forums
  • Automated Signatures
    On Your Posts
  • Best Of All, It's Free!

*Tek-Tips's functionality depends on members receiving e-mail. By joining you are opting in to receive e-mail.

Posting Guidelines

Promoting, selling, recruiting, coursework and thesis posting is forbidden.

Students Click Here

Trcky indirect memory address

Trcky indirect memory address

Trcky indirect memory address

(OP)
Hi fellas,
I have some in the text book "Assembly Language for INtel-based Computer" 4th ed.
Page 127
.data
myDoubles DWORD 1,2,3,4,5
myPointer DWORD myDoubles

So, can anybody know what the following codes will do:
.code
mov ax,WORD PTR [esi+2] ; AX=?
mov ax,WORD PTR [esi+6] ; AX=?
mov ax,WORD PTR [esi-4] ; AX=?

I even try to assembly them in MASM, but it crashed when I debugged it in CodeView.
Thanks pal.

RE: Trcky indirect memory address

No one would know, for the simple reason that no one would know what the value of the esi register is.  Show us what esi is initialized to.  Read the book, I'm sure it explains what the instructions would do.  Quite likely you got some sort of General Protection Fault since esi was by chance larger than 0ffffh and you are in 16-bit programming.

"Information has a tendency to be free.  Which means someone will always tell you something you don't want to know."

RE: Trcky indirect memory address

(OP)
Sorry fella, it's my fault
ESI is set to:
mov esi,myPointer

IN other words, esi is now contains the offset of myDoubles.
Thank you.

Red Flag This Post

Please let us know here why this post is inappropriate. Reasons such as off-topic, duplicates, flames, illegal, vulgar, or students posting their homework.

Red Flag Submitted

Thank you for helping keep Tek-Tips Forums free from inappropriate posts.
The Tek-Tips staff will check this out and take appropriate action.

Reply To This Thread

Posting in the Tek-Tips forums is a member-only feature.

Click Here to join Tek-Tips and talk with other members! Already a Member? Login


Close Box

Join Tek-Tips® Today!

Join your peers on the Internet's largest technical computer professional community.
It's easy to join and it's free.

Here's Why Members Love Tek-Tips Forums:

Register now while it's still free!

Already a member? Close this window and log in.

Join Us             Close