IBM GA24-3312-9 2821 Unit Description Oct82 free download

File name GA24-3312-9_2821_Unit_Description_Oct82.pdf

GA24-3312-9 File No. 2821-03 IBM 2821 Control Unit Systems Component Description --- - - --- -- - - - - - -,,- -- --- --.-... - - - -~- ----- -~--- Federal Communications Commission (FCC) Statement Waming: This equipment generates, uses, and can radiate radio- frequency energy and, if not installed and used in accordance with the instructions manual, may cause interference to radio communications. It has been tested and found to comply with the limits for a Class A computing device pursuant to Subpart J of Part 15 of FCC Rules, which are designed to provide reasonable protection against such interference when operated in a commercial environment. Operation of this equip- ment in a residential area is likely to cause interference. In which case, the user, at his own expense, is required to take whatever measures may be necessary to correct the interference. The FCC statement above refers to machines manufactured or reconditioned since 1 January 1981. PREFACE This reference publication for system planners, programmers, and operators presents a description of input/output operations controlled through the IBM 2821 Control Unit. The IBM 2540 Card Read-Punch and the IBM 1403 and 1404 Printers controlled by the IBM 2821 Control Unit are briefly described. Commands, status and sense information pertaining to the attached input! output units is presented. Programming timing considerations for control unit, card reader, card punch, and printers are also presented. For further information about the attached input/output units, refer to: IBM 2540 Card-Read Punch, Order No. GA21-9033, IBM 1403 Printer, GA24-3073, and IBM 1404 Printer, GA24-1446. For further information about input/output and channel operations, refer to: IBM System/3 60 Principles of Operation, GA22-6821, and IBM System/3 70 Principles of Operation, GA22-7000. Other related literature is listed in the System/360 and System/3 70 Bibliography, GA22-6822. Tenth Edition (October 1982) This is a reprint of GA24-3073-8, incorporating changes released in Technical Newsletter GN24-0898 (31 December 1980). Information in this publication is subject to change. Before using this publication be sure you have the latest edition and any Technical Newsletters. Copies of this and other IBM publications can be obtained through IBM branch offices. This manual has been prepared by the IBM General Technology Division, Product Publications, Dept. KlO, P.O. Box 6, Endicott, N.Y. 13760. CONTENTS IBM 2821 CONTROL UNIT. 5 Special Features. . .