Yes of course.
may use the area from 08h through 2Fh as a general purpose RAM with the direct method:

MOV 2FH, #23H               ; stores the value 23h to RAM position 2F

 

or the indirect method:

MOV R0, #2FH               ; load the R0 index register with the desired RAM position
MOV @R0, #23H              ; store the value 23h to the RAM position pointed to by R0 index

 

The assembly intructions are pretty straighforward, don't be confused.
Actually the last year random numbers generator was a difficult task. This is basics.
Have in mind that post: http://www.8052.com/forum/read/166982
Since you write the application in assembler it is obvious that there is not exist
an active Operating System to set priorities and certain form of actions to the memory area
that you have to follow.

K.L.Angelis