A system, computer readable medium and a method of operating a non volatile memory (NVM) array that comprises multiple NVM cells, the method comprises: receiving input data to be written to the non volatile memory; performing constraint coding on the input data to provide encoded data; wherein the constraint coding prevents the encoded data from comprising forbidden combinations of values; wherein the forbidden combinations of values are defined based on expected inter-cell coupling induced errors resulting from coupling between NVM cells; and writing the encoded data to the non volatile memory.