Browse Prior Art Database

Manual Controls for a Read Only Store Controlled Computer

IP.com Disclosure Number: IPCOM000094429D
Original Publication Date: 1965-Jan-01
Included in the Prior Art Database: 2005-Mar-06
Document File: 3 page(s) / 45K

Publishing Venue

IBM

Related People

Sarubbi, JA: AUTHOR [+2]

Abstract

In order to sense and respond to manually operated buttons 1 on computer control panel 2, with effective precautions against accidental misuse and with efficient utilization of otherwise idle, or available system components, the buttons are sensed by basic microprogram controls 3 of the computing system only at predetermined system states.

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Manual Controls for a Read Only Store Controlled Computer

In order to sense and respond to manually operated buttons 1 on computer control panel 2, with effective precautions against accidental misuse and with efficient utilization of otherwise idle, or available system components, the buttons are sensed by basic microprogram controls 3 of the computing system only at predetermined system states.

Controls 3 include a set of permanently stored basic microinstructions. These are linked together sequentially, in consecutive periods of operation of the controls, to produce basic microprograms for controlling the various functions of the system. The controls operate periodically, at intervals of one half microsecond, in response to clock pulses produced by clock 4. In each such period of operation a new microinstruction is fetched from the control storage and controls the issuance of numerous basic control signals or micro-orders.

A line carrying one such micro-order MO is shown at 5. This particular micro- order occurs only during execution of a particular microprogram known as a Halt Loop. Having completed a segment of another particular microprogram known as I-Fetch, because its function is to retrieve a major, i. e., macroprogram system instruction from working storage, controls 3 examine an exception signal Exc. This is activated only if the computer is in a special state due to a pending channel or external interrupt, or to a halt signal or to a wait bit in a Program Status Word, or to manipulation of a Stop button. If Exc is not active, the controls proceed in the normal, or ordinary, microinstruction sequence, but if Exc is active the controls branch to the Halt Loop.

As indicated by dotted lines 6, push buttons 1 control associated switch contacts 7. These control the coupling of signal V to encoding unit 8. Encoder 8 is in turn controlled by the MO micro-order s...