8051 Programme to store the higher nibble of r7 in to both nibbles of r6

Statement : - store the higher nibble of r7 in to both nibbles of r6

Solution: –first we shall get the upper nibble of r7 in r6. Then we swap nibbles of r7 and make OR operation with r6 so the upper and lower nibbles are duplicated       



      

Mov a, r7                     ; get the content in acc

                        Anl a, #0F0h                ; mask lower bit

                        Mov r6, a                     ; send it to r6

                        Swap a             ; xchange upper and lower nibbles of acc

                        Orl a, r6                       ; OR operation

                        Mov r6, a                     ; finally load content in r6