Input Output Subsystem

The I/O subsystem connects the system to its peripheral devices using the industry standard 32-bit peripheral component interface (PCI) bus. A fully configured system provides up to eight PCI buses, one for each EPAC. Each bus supports three controllers for a maximum of 24 PCI controllers for the system

Input Output Devices

The term I/O is used to describe any program, operation or device that transfers data to or from a computer and to or form a peripheral device. Every transfer is an output from one device and an input into another. Devices such as keyboards and mouse are input-only devices while devices such as printers are output-only. A writable CD-ROM is both an input and an output device.