A request to perform a data operation associated with at least one memory unit in a plurality of memory units of a memory device is received. The at least one memory unit includes a first group of memory cells, each memory cell supporting a specified number of charge levels such that each memory cell having the specified charge level represents a non-integer number of bits. The first group of memory cells represents a first sequence of bits based on a first sequence of charge levels formed by the first group of memory cells. The data operation is performed with respect to the at least one memory unit based on a mapping stored on the system. The mapping assigns an individual sequence of charge levels from an individual group cell to an individual sequence of bits represented by the individual group of memory cells.