Peripheral devices store data in non-volatile phase-change memory (PCM). PCM cells have alloy resistors with high-resistance amorphous states and low-resistance crystalline states. The peripheral device can be a Serial AT-Attachment (SATA) or integrated device electronics (IDE) PCM solid-state disk or a Multi-Media Card/Secure Digital (MMC/SD) card. A peripheral PCM controller accesses PCM mass storage devices containing PCM memory chips that form a mass-storage device that is block-addressable rather than randomly-addressable. SATA, IDE, or MMC/SD transactions from a host bus are read by a bus transceiver on the peripheral PCM controller. Various routines that execute on a CPU in the peripheral PCM controller are activated in response to commands in the host-bus transactions. A PCM controller in the peripheral controller transfers data from the bus transceiver to the PCM mass storage devices for storage.