Browse Prior Art Database

Interrupt Driven Real Time Multiprogram Supervisor for a Data Collection System

IP.com Disclosure Number: IPCOM000077525D
Original Publication Date: 1972-Aug-01
Included in the Prior Art Database: 2005-Feb-25
Document File: 5 page(s) / 95K

Publishing Venue

IBM

Related People

Felix, RA: AUTHOR

Abstract

A vital part of a computer-centered data-collection system (DCS) is the supervisor program resident in the computer. The supervisor's main job is to process as many external interrupts as possible. This processing involves accepting the data provided by a remote source and then either: Passing the data to the appropriate working program (also resident in the computer), or Disposing of the data if the appropriate working program has no need of it.

This text was extracted from a PDF file.
At least one non-text object (such as an image or picture) has been suppressed.
This is the abbreviated version, containing approximately 35% of the total text.

Page 1 of 5

Interrupt Driven Real Time Multiprogram Supervisor for a Data Collection System

A vital part of a computer-centered data-collection system (DCS) is the supervisor program resident in the computer. The supervisor's main job is to process as many external interrupts as possible. This processing involves accepting the data provided by a remote source and then either: Passing the data to the appropriate working program (also

resident in the computer), or

Disposing of the data if the appropriate working program has

no need of it.

This article presents a general description of one such supervisor. A companion article (IBM Technical Disclosure Bulletin, Volume 15, Number 3, pages 861 - 864 published August 1972) describes an implementation of external interrupt handling by the supervisor. A basic DCS is depicted in Fig. 1.

The following are features of this supervisor which other available supervisors either do not provide, or provide at the expense of allowing the supervisor to use 20K (or more) bytes of main storage.
1) Dynamic reassignment of I/O devices based on requests made

by working programs. A queue of I/O usage requests is also

maintained.
2) Operation with as many working programs as can fit into

main storage. The supervisor itself requires less than 9K.
3) Routing of external interrupts to the appropriate working

program. If the working program is busy analyzing previously

collected data, the supervisor disposes of the interrupt and

its associated data. At times the supervisor itself is

externally interruptible.
4) A program check in a working program causes several lines

of descriptive data on the system console and disables the

failing program. A storage dump is not provided.
5) Working programs function in the supervisor state.

Instructions customarily privileged to the supervisor can be

issued

by any working program. An example of this is the use of

the LPSW (Load Program Status Word) instruction to transfer

control from working programs.

Because working programs operate in the supervisor state, they are essentially extensions of the supervisor. Each working program is structured as follows: Initialization Routines

External Interrupt Data Handling Routines

Data Analysis and Output Routines

The primary initialization routine causes the supervisor to read the control cards that define:

1

Page 2 of 5

Which external interrupts are to be routed to the working

program, and

How the supervisor is to read the data provided by each

external interrupt.

In this way the different types of data generated by

different instruments can be accommodated.

The secondary initialization routine requests the supervisor to activate its external interrupt data handling routines, by modifying the branch instruction that begins each of these routines. This process is commonly initiated by a manually generated external interrupt at one of the Remotes.

Each external interrupt data handling routine:

Begins with a branch instruction that acts as a gate...