Programmed input–output
TERM
Programmed Input/Output; PIO Mode; Port-mapped IO; Programmed I/O; PIO mode; Programmed IO; Programmed i/o; Programmed input/output; Programmed input-output
Programmed input–output (also programmable input/output, programmed input/output, programmed I/O, PIO) is a method of data transmission, via input/output (I/O), between a central processing unit (CPU) and a peripheral device, such as a Parallel ATA storage device. Each data item transfer is initiated by an instruction in the program, involving the CPU for every transaction.