How to write 0.5 in assembly language code?

Question

How can I convert the floating point "0.5" into a fixed point digit suitable for an assembly code?

Thank you for your answer,

Edit: I am trying to multiply the contents of AX by half, so I wrote IMUL AX,AX,0.5

The assembler refused this and told me "floating-points are not allowed".

All that I want is to divide the contents of AX by two.

This will depend on what you want to do with it. Assemblers know nothing about fixed point numbers (unless you're trying to use a floating-point extension) so, do what you like. — , Apr 17 '14 at 08:42
Floating-point is implemented by specific instructions on the majority of modern processors. Fixed-point has to be implemented by hand using integer instructions. Especially if you are writing in assembly, you should be using floating-point. And your question lacks enough detail to be answerable anyway. — Pascal Cuoq, Apr 17 '14 at 08:42
Ok, that's a lot different now. Do you want to interpret `AX` as signed or as unsigned? — harold, Apr 17 '14 at 08:49

score 0 · Accepted Answer · answered Apr 17 '14 at 08:59

0

Signed:

cwd
sub ax, dx
sar ax, 1

Unsigned:

shr ax, 1

answered Apr 17 '14 at 08:59

harold

1 Answers1