公开(公告)号：US3673575A

公开(公告)日：1972-06-27

申请号：US3673575D

申请日：1970-06-29

Applicant: IBM

Inventor： BURTON PAUL T ,  COLE WALTER E ,  FRASSETTO HENRY E JR ,  GIBSON ROBERT G ,  GREENBERG ALLAN ,  HANDLOFF LOUIS E ,  RADLINSKY RAYMOND

IPC: G06F9/26 ,  G06F9/00

CPC classification number: G06F9/267

Abstract: A microprogrammed common control unit for effecting the transfer of data between I/O (input/output) devices and the main storage unit of a data processing system, uses both long format control words and short format control words, the short words having half as many bit positions as the long words in the preferred embodiment, thereby minimizing the size of control storage required. Addressing of the control storage unit effects readout of one long word or a pair of short words. Predetermined bits in each control word cause transfer of a first part (half) of the next accessed long word or either one of a next accessed pair of short words to a control register for execution. If a long word has been accessed, one of said bits is effective during execution of the first part of the long word to initiate the transfer of the second word to the control register for execution after the termination of the execution of the first part of the word. Consecutive decode of the first and second portions of a long word permits a smaller control register and substantial sharing of decode circuits by different long format control word fields entered into at least partially corresponding positions of the control register, thereby effecting substantial economies.

Abstract translation: 用于在I / O（输入/输出）设备和数据处理系统的主存储单元之间进行数据传输的微程序公共控制单元使用长格式控制字和短格式控制字，短字具有一半 许多比特位置作为优选实施例中的长字，由此最小化所需的控制存储器的大小。