Programmed Input/Output [PIO] Can refer to MMIO (memory mapped I/O) or PMIO (port-mapped I/O) To access this content, you must purchase a Membership - check out the different options here. If you're a member, log in. Tags: Embedded, Processor Peripheral « Back to Glossary IndexRelated Terms:Glossary: Memory-Mapped I/OGlossary: Input/OutputGlossary: Port-Mapped I/O