To test all of RAM, use indirect addressing exclusively. Use MOV @R0 as opposed to MOV addr.

I'd suggest using R0 as your pointer and testing each address from 01h through FFh. When you're done, test 00h manually.

Just remember that when you modify addresses 00h through 07h, you're modifying R0 through R7. If you're using those registers in the code that is executing the test you'll inevitably end up overwriting them during the test itself.

Depending on how complex your test code is, you may have to test addresses 08h through FFh and then switch to register bank 1 and run the test for 00h through 07h.

Regards,
Craig Steiner