My Question is how can the controller now when he interpretes this code that for example
the code 52 is the letter R and not the command: ANL Daddr,A .How does he make the switch
to know if it is the command or the data character.

It does not need to 'know'. only places accessed through the code is interpreted as code. Only data accessed by MOVC is interpreted as data.

Erik

PS your ode is never going tp run with no jmp at 0