IBM GA22-6942-1 370-155 funcChar Jan71 free download

File name GA22-6942-1_370-155_funcChar_Jan71.pdf

IBM System/370 Model 155 Systems Functional Characteristics This publication describes the organization, functional characteristics, and features of the IBM System/370 Model 155. System components are described, and consideration is given to the central processing unit, main storage, input/output channels, and the operator control and operator intervention portions of the system control panel. This publication is intended for users and potential users of the Model 155. The reader is assumed to have a background knowledge of data processing systems. Preface This is the Model 155 machine reference manual, providing information about system and component functions and addressing an audience made up primarily of system analysts, programmers, and operators. Assumed is a back- ground knowledge of data processing systems and of the System/370 and System/360, as provided in IBM System/ 370 Principles of Operation, GA22-7000, and IBM System/ 360 Principles of Operation, GA22-6821. The manual first looks at the system and its features in general, then at the processing unit and its functions. Channel characteristics are discussed in some detail, includ- ing channel control and implementation, sub channel and unit control word definitions, and subchannel addressing. This is followed by a description of system control panel functions and commonly used indicators, switches, and keys, then by information about the console I/O unit characteristics and the alter/display feature. Detailed information about channel loading characteris- tics is in a separate manual: IBM Systerrz/370 Model 155 Channel Characteristics, GA22-6962. Second Edition (January 1971) This is a major revision of, and obsoletes, GA22-6942-0. Changes to the text are indicated by a vertical line to the left of the change; changed illustrations are denoted by the symbol. to the left of the caption. Changes are continually made to the specifications herein; before using this publication in connection with the installation and operation of IBM equipment, refer to the latest System/360 and SY,stem/370 SRL Newsletter, GN20-0360, for editions that are applicable and current. Requests for copies of IBM publications should be made to your IBM representative or to the IBM branch office serving your locality. This manual has been prepared by the IBM Systems Development Division, Product Publications, Dept. B98, PO Box 390, Poughkeepsie, N.Y. 12602. A form fur readers' wmments is pruvided at the Lack uf this publicatiun. If the form has been removed, comments may be sent to the above address.