Wand for reading and writing information to electronic tokens

Details Wand for reading and writing information to electronic tokens Wand for reading and writing information to electronic tokens

1994-12-13

1997-05-06

Pitts, Harold

Registers

Coded record sensors

Particular sensor structure

235441, 235492, G06K 710

Patent

active

056273614

ABSTRACT:
A system architecture which provides efficient data communication, over a one-wire bus, with a portable data module which does not necessarily include any accurate time delay circuit whatsoever. The time delay circuit in the module can be extremely crude. An open-collector architecture is used, with electrical relations defined to absolutely minimize the drain on the portable module's battery. A protocol has been specified so that the module never sources current to the data line of the one-wire bus, but only sinks current. The protocol includes signals for read; write-zero; write-one; and reset. Each one-bit transaction is initiated by a falling edge of a voltage signal from the host. The time delay circuit in the module defines a delay, after which (in write mode) the module test the data state of the data line. In read mode, after a falling edge of a voltage signal from the host the module does or does not turn on a pull-down transistor, depending on the value of the bit read. Thus, the host system, after the falling edge, attempts to pull the data line high again, and then tests the potential of the data line to ascertain the value of the bit read.

REFERENCES:
patent: 3846971 (1974-11-01), Ho et al.
patent: 3996735 (1976-12-01), Zurcher
patent: 4028682 (1977-06-01), Weber et al.
patent: 4040026 (1977-08-01), Gernelle
patent: 4053688 (1977-10-01), Perkins et al.
patent: 4064689 (1977-12-01), Yasuda et al.
patent: 4086752 (1978-05-01), Kishimoto
patent: 4196577 (1980-04-01), Ohno et al.
patent: 4217637 (1980-08-01), Faulkner et al.
patent: 4241418 (1980-12-01), Stanley
patent: 4272838 (1981-06-01), Kasama et al.
patent: 4295220 (1981-10-01), Blum et al.
patent: 4337525 (1982-06-01), Akatsuka
patent: 4396985 (1983-08-01), Ohara
patent: 4400711 (1983-08-01), Avery
patent: 4426159 (1984-01-01), Kosaka et al.
patent: 4475178 (1984-10-01), Kinoshika
patent: 4486770 (1984-12-01), Woodward
patent: 4509120 (1985-04-01), Daudelin
patent: 4556958 (1985-12-01), Ugon
patent: 4558435 (1985-12-01), Hsieh
patent: 4595941 (1986-06-01), Avery
patent: 4616343 (1986-10-01), Ogawa
patent: 4631567 (1986-12-01), Kokado
patent: 4713555 (1987-12-01), Lee
patent: 4717817 (1988-01-01), Grass
patent: 4780707 (1988-10-01), Selker
patent: 4862310 (1989-08-01), Harrington, III
patent: 4868409 (1989-09-01), Tanaka et al.
patent: 4945217 (1990-07-01), Bolan
patent: 4980746 (1990-12-01), Harrington, III
patent: 4983820 (1991-01-01), Dias
patent: 5025141 (1991-06-01), Bolan

Affiliated with

Also associated with

Rating

Wand for reading and writing information to electronic tokens does not yet have a rating. At this time, there are no reviews or comments for this patent.

If you have personal experience with Wand for reading and writing information to electronic tokens, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Wand for reading and writing information to electronic tokens will most certainly appreciate the feedback.

Rate now

Comments { 0 }

Profile ID: LFUS-PAI-O-2134276