Abstract:
The specification discloses an illustrative embodiment for the invention comprising a large-scale data processing system of the type which is composed of a plurality of quasi-independent units. The environmental data processing system includes a central processing unit or portion, which is herein referred to as a CPU, a plurality of storage units, a plurality of input/output control devices referred to herein as channels, as well as control and maintenance facilities which are found in a power distribution unit, herein referred to as a PDU. The CPU of the environmental system includes a control or instruction unit hereinafter referred to as an I-unit, and an arithmetic and logic or execution unit, hereinafter referred to as an E-unit. The I-unit includes controls for instruction fetching, branching, interruption handling, communication with the input/output channels, and other related functions. The E-unit of the environmental system can perform algebraic and logical operations, moving, shifting, and other functions.