Browse Prior Art Database

Self Checking Control Logic

IP.com Disclosure Number: IPCOM000095081D
Original Publication Date: 1965-Sep-01
Included in the Prior Art Database: 2005-Mar-07
Document File: 2 page(s) / 40K

Publishing Venue

IBM

Related People

MacDougall, JP: AUTHOR [+2]

Abstract

The system transfers information between a serial source such as a magnetic tape drive and a parallel source such as a computer. Converters 3 and 4 receive information at a serial read input and produce the parallel outputs. They also receive information at the parallel inputs and energize a serial write output. Each converter also does error checking. Such a system also includes counter 5. This responds to input pulses to establish a time delay for accelerating a motor that drives the serial information source. In the system, these components are used to perform checks when the tape drive is idle or is accelerating.

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 57% of the total text.

Page 1 of 2

Self Checking Control Logic

The system transfers information between a serial source such as a magnetic tape drive and a parallel source such as a computer. Converters 3 and 4 receive information at a serial read input and produce the parallel outputs. They also receive information at the parallel inputs and energize a serial write output. Each converter also does error checking. Such a system also includes counter 5. This responds to input pulses to establish a time delay for accelerating a motor that drives the serial information source. In the system, these components are used to perform checks when the tape drive is idle or is accelerating.

For checking, the serial inputs and outputs of converters 3 and 4 are interconnected so that each can receive the serial output of the other. The parallel inputs of a selected one of the two converters is connected to receive a character generated by counter 5. The selected converter converts the character to serial form at the write output. The other converter receives the serial character at its read input and produces it in parallel form at its parallel output. If there is no error, the character is unchanged by this operation.

Counter 5 has four sections A... D. Sections A... C operate the circuit for checking. Section D provides the count for the motor operation and is not related to the checking operation. If the motor is not to be energized at the end of the delay, the counter recycles and the check continues.

Secti...