• C

Turn Off Caps Lock (Dos C Program)

I have a c DOS program running on an old 386 and need to turn off the caps lock. How do I do this? (C or Assembly)
mikeuAsked:
Who is Participating?
I wear a lot of hats...

"The solutions and answers provided on Experts Exchange have been extremely helpful to me over the last few years. I wear a lot of hats - Developer, Database Administrator, Help Desk, etc., so I know a lot of things but not a lot about one thing. Experts Exchange gives me answers from people who do know a lot about one thing, in a easy to use platform." -Todd S.

mikeuAuthor Commented:
Adjusted points to 200
0
rbrCommented:
To change the status of your keyboard you have the change to bios-values at 0x0040:0x0017

set_flag (int flag)
{
    char far *pflag;

    pflag = (char far *) (((unsigned long)0x40)<<16+(unsigned long) 0x17);

    *pflag |=flag
    _asm {
        mov ah,1
        int 16h
     }
}
clear_flag (int flag)
{
    char far *pflag;

    pflag = (char far *) (((unsigned long)0x40)<<16+(unsigned long) 0x17);

    *pflag &= ˜flag;
    _asm {
        mov ah,1
        int 16h
     }
}

flag = 16 Scroll lock
flag = 32 Num Lock
flag = 64 Caps Lock
0

Experts Exchange Solution brought to you by

Your issues matter to us.

Facing a tech roadblock? Get the help and guidance you need from experienced professionals who care. Ask your question anytime, anywhere, with no hassle.

Start your 7-day free trial
mikeuAuthor Commented:
when I try your example in code view the value of the pointer pflag seems to be 0000:2000  not 0040:0017 ?!? am I just being stupid and missing something? Thanks for any Info
0
Increase Security & Decrease Risk with NSPM Tools

Analyst firm, Enterprise Management Associates (EMA) reveals significant benefits to enterprises when using Network Security Policy Management (NSPM) solutions, while organizations without, experienced issues including non standard security policies and failed cloud migrations

mikeuAuthor Commented:
This works pflag = (char far *)0x00000417L

0
mikeuAuthor Commented:
Very strange behavior. Which compiler to you use?
0
rbrCommented:
Sorry, was a mistake of my book. Use instead of "<< 16" "* 16L" or "<< 4". This should work.
0
rbrCommented:
I use Microsoft vc++ 1.52 for my dos stuff and 5.0 for windows.
I tried the *16L and it seems to work.
Thanks for your help
0
It's more than this solution.Get answers and train to solve all your tech problems - anytime, anywhere.Try it for free Edge Out The Competitionfor your dream job with proven skills and certifications.Get started today Stand Outas the employee with proven skills.Start learning today for free Move Your Career Forwardwith certification training in the latest technologies.Start your trial today
C

From novice to tech pro — start learning today.

Question has a verified solution.

Are you are experiencing a similar issue? Get a personalized answer when you ask a related question.

Have a better answer? Share it in a comment.