A memory device includes a memory array having multiple nonvolatile memory cells that stores data as a set or a reset state of the memory cells. The nonvolatile memory cells can be resistance-based memory, which stores data based on resistive state of the memory cells. A controller coupled to the memory array periodically samples set and reset margins for memory cells of the memory array. Responsive to detection of a change in a margin, the system can adaptively adjust a preset electrical setting used to differentiate between a set state and a reset state.