WRSB: MOV 0A2H, #0  ;Clr the Enboot bit
      MOV R0, #6    ;Fosc - your crystal freq. here
      MOV R1, #06H  ;program status byte 
      MOV DPTR, #0  ;specify status byte
      MOV A, #0     ;zero status byte for code execution
      CALL 0FFF0H   ;execute the function