We help IT Professionals succeed at work.

getvet(),setvector() how were made in assembler language??

uart8250 asked
Last Modified: 2011-09-20
 i need know how the getvect() and setvec() "C/C++" functions were made in assembly language ??  
(by example MS-Macro Assembler , MASM)
please writte the assembly code!!!!

Thanks again!!
Watch Question

Why?  If you are running on a platform that supports them (like I suspect win16 does) then use the C/C++ version.  If not, you can't use assembly version either.

I have no documenation for the functions since they are not available in win32, but if you describe them I could write them for you.  Note however, that they can't be run from win32.
Unlock this solution and get a sample of our free trial.
(No credit card required)

To get the address of interrupt 21h
mov ax, 3521h
int 21h
; DS is the segment
; DX is the offset

To set the address of interrupt 21h
mov ax, 2521h
; NewISR21 is the ISR you want to use instead of the current handler
mov es, seg NewISR21
mov bx, ofs NewISR21
int 21h


Thanks Bonev... Now,  what I can do?? becouse, I use Visual C/C++  5.0 (32bits) and
I need the setvect( ) , getvect( ) functions.

Thanks Again!!


Thanks nietod... Now, What I can do?? becouse , I use Visual C/C++ (32bits) and
I need the setvect( ), getvect( ) functions!!   any idea??

Thanks Again!!

Is your program MS-DOS based or not?

What can I do?  Well for a start, you can try to obtain a working answer rather than accepting one that is useless...

The problem is that interrupts really can't be used by an application in a protected mode environment.  The OS won't allow you to alter the interrupt dispatch table.  And even if you could alter it, your program (and most likely the whole system) would crash when the interrupt is called anyways.  The operating system and device drivers can use interrupts, but that is a different matter.  They are designed to be able to handle them.

What is it that you are hoping to do.?

The program is a 32 bit windows program.  That is the only thing that VC 5 can produce.  If it wasn't a 32 bit program, then he could just use the getvect.setvect functions.  
Unlock the solution to this question.
Thanks for using Experts Exchange.

Please provide your email to receive a sample view!

*This site is protected by reCAPTCHA and the Google Privacy Policy and Terms of Service apply.


Please enter a first name

Please enter a last name

8+ characters (letters, numbers, and a symbol)

By clicking, you agree to the Terms of Use and Privacy Policy.