There is disclosed systems and methods for testing a memory where at least one bit field at certain address locations cannot be directly accessed. In one embodiment, random bits are populated into a data field at one of the certain address locations, and at least some of the random data bits that are copied into non-directly accessible data field. The bits which were copied from the data field are replaced with bits resulting from X/ORing the copied data bits with bits read from the non-directly accessible field, and all the data field bits as the address locations are checked for mismatched data bits.