A method to operate a single bit per cell memory comprises erasing a group of memory cells establishing a first logical value by setting threshold voltages in a first range of threshold voltages. First writing, after said erasing, includes programming first selected memory cells to establish a second logical value by setting threshold voltages in a second range of threshold voltages, and saving a sensing state parameter to indicate a first read voltage. Second writing, after said first writing, includes programming second selected memory cells to establish the second logical value by setting threshold voltages in a third range of threshold voltages, and saving the sensing state parameter to indicate a second read voltage. After a number of writings including said first writing and said second writing reaches a threshold number for writing the group of memory cells, the group of memory cells can be erased.