I/O Driver Mode
Original Publication Date: 1980-May-01
Included in the Prior Art Database: 2005-Feb-13
In contemporary data processing systems, operations of multiple I/O channels are conducted through a shared processor, termed the Director, which generally operates on an asynchronous basis relative to central processors of the same system. Each Director is usually a self contained processor having extensive capacity for logic and buffer storage functions. Typically, a Director is controlled by microprograms which are retained in a buffer control store on a volatile or alterable basis. Such micro-programs are usually loaded into the Director control store from an external non-volatile storage medium--e.g., a disk--under control of a service processor which initializes the central and I/O processing subsystems.