The IBM System/370 Model 158 was a medium-size, high performance data processing system that incorporated integrated monolithic main storage, virtual storage capability, integrated storage controls, and a display console. These functional capabilities made possible expanded applications for large-scale users.
The basic components of the System/370 Model 158 were the IBM 3158 Processing Unit, the display console, and an optional console printer. A large number and variety of storage and communication devices could be attached.
Summary of characteristics
General upward compatibility with most System/360 architecture and programming was maintained through implementation of the basic control (BC) mode of system operation. An extended control (EC) mode of operation was also supported. When the Model 158 operated in EC mode, the program status word (PSW) format and the layout of permanently assigned lower processor storage were altered to support additional system control and functions, such as dynamic address translation.