Question

I was playing around with assembly, compiling to .com files using NASM on Windows 7. For some reason, this doesn’t work:

org 100h
run1:
mov ax, 3
int 33h
cmp bx, 0
je run1
xor bx, bx
run2:
mov ax, 3
int 33h
cmp bx, 0
je run2
int 20h

I think this should repeat run1 until there is a mouse click, and then do the same with run2. Then, the program should quit. But, when I execute the program, it only waits for one mouse click.
What do I need to do to fix this?
Thanks in advance

Answer 1

I believe this will do it (with comments).
(code is untested)

Basically, there are now 3 loops.
1.) Wait for the button to be pressed.
2.) Wait for the button to be released.
3.) Wait for the button to be pressed again.

org 100h
run1:
mov ax, 3
int 33h     #Check the mouse
cmp bx, 0   #See if button is pressed
je run1     #If Not pressed, go back and check again

xor bx, bx  #Okay, button is pressed, clear the result

run1a:
mov ax, 3
int 33h     #Check the mouse
cmp bx, 0   #See if button is released
jne run1a   #If NOT equal, then not released, go check again.

xor bx, bx  #button is released, clear the result

run2:
mov ax, 3
int 33h     #Check the mouse
cmp bx, 0   #if button is pressed (2nd time)
je run2     #If NOT pressed, go to top.

int 20h     #Button was pressed.  All done (we don't care when its released)