Receive data hardware

can i receive data from hardware to my arduino using RS232 with TTL ?

If the "hardware" has RS232 then yes, absolutely.

To communicate between RS232 serial and TTL serial you need a conversion chip such as a MAX232. RS232 voltages can damage an Arduino.

...R

Ah, yes of course. Somehow, I was suppose it is obvious but it is not. @Robin2++