how dose byte to string really works

[HELLFIX]

why do you need to mask the upper 12 bits


and     DI, 000Fh  ;Mask out the unwanted
                   ;high 12 bits by setting
                   ;them to 0 leaving the
                   ;low 8 bits conserved as
                   ;been copied from AX,
                   ;lets say we copied 0ABh
                   ;to AL this instruction
                   ;will make DI look like
                   ;this: DI=000B;

i want to know why exactly do you need to do this
which part of the example code its it converting bytes to string

and  is there a simpler way
to convert byte to string

[Frank Kotler]

I suppose you're looking at Shikatsu's example?

http://forum.nasm.us/index.php?topic=1335.0

In any case, we probably want a 16-bit register so we can add it to another 16-bit register, but we only want the value of a single digit. The comment you show isn't quite correct - only four bits remain in the result, not eight.

There's a "logical" or "boolean" and, in which the result is "true" (non-zero) if both operands are "true" - "false" (zero) is either or both are "false". The "and" instruction works on a bitwise basis - a bit in the result is 1 if the corresponding bits in both operands are 1, the bit is 0 if either or both bits are zero. In this case, the result has a numeric value, not just "true" or "false".

There are a number of ways to convert byte (or larger value) to a string... and the number can be represented as decimal or hex... or other. "Just call printf" is pretty simple - the code to printf isn't simple, but someone else wrote it!

Maybe if you tell us more about what you're trying to do, or exactly which code you're looking at, we can be more help. Wait'll you see floating point!

Best,
Frank

[HELLFIX]

oh ok i see what you mean i want to know how to convert a byte to string so i can print it on to the screen. i dont know how to include printf if in nasm
i tried masm but it does not work eithers so im sticking with nasm for assembly programming

[HELLFIX]

Thanks again frank i understand how to convert byte to string using the sample code