Browse Prior Art Database

Statistical Byte Manipulation

IP.com Disclosure Number: IPCOM000084094D
Original Publication Date: 1975-Sep-01
Included in the Prior Art Database: 2005-Mar-02
Document File: 2 page(s) / 13K

Publishing Venue

IBM

Related People

Bowles, DJ: AUTHOR

Abstract

A printer may be controlled by metal-oxide semiconductor (MOS) chips; a random-access memory, a processor, and a read-only storage.

This text was extracted from a PDF file.
This is the abbreviated version, containing approximately 53% of the total text.

Page 1 of 2

Statistical Byte Manipulation

A printer may be controlled by metal-oxide semiconductor (MOS) chips; a random-access memory, a processor, and a read-only storage.

The printer may store tab stops in a volatile random-access memory which is accessed by the processor. When power is turned off from this memory the tab stops are destroyed. To solve this functional problem, two switches can be installed on the printer. One switch (A) is used to control AC supply voltage to the printer and the other switch (B) is used to turn off only the motor and magnets.

The operator can turn the motor (switch B) off and the machine has the appearance of being off. When switch B is off, power remains on the processor and random-access memory. Thus the tabs are remembered and when switch B is turned on, the operator has the same tabs and margins as before the machine was turned off.

When switch A or B is closed, the processor is started at address zero by the hardware so that the printer can be synchronized with the processor.

When switch A is transferred from open to closed, the program should clear out the tab storage, because the random-access memory is meaningless since power has been off.

When switch B is transferred from open to closed with switch A closed, the program should save the existing storage since power has remained on the chips.

The program needs to know the past history of switch A and switch B. This is done by the following method. When switch A is transferred from open to closed, the random-access memory will come up in a random fashion (any possible byte pattern). Dedicated bytes of the random-access memory are now co...