US5121482A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Circuit and method for automatic input-output configuration through local area network detection
Assignee: HP Inc
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Filing: 1989-09-11
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Granted: 1992-06-09
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Expires: 2009-09-11
Abstract
Abstract The invented circuit includes an I/O driver capable of supplying current to an I/O connector, a current detection circuit that may include a current limit resistor and a differential amplifier, a comparator to compare the level of current to a predetermined level and to produce an output signal based thereon, and a translator to convert the output signal from the comparator into a transistor-transistor logic signal. The device that includes the invented circuit then interprets the logic signal as identifying either a serial I/O system or a LAN I/O system.
Inventors
- 👤 David B. Patton
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-30 18:40
CPC Classifications
H; H04; H04L; H04L12/00; H04L12/28
Claims Analysis
Total Claims: 12
Claim 1
Independent Claim
130 words
Apparatus capable of differentiating between a connected serial input-output (SERIO) system and a connected local area network input-output (LANIO) system, said apparatus comprising: an input-output connector adapted for connection selectively to such a SERIO or LANIO system; driver means operatively connected to said connector for supplying a signal to the connector and by way of said connector to a connected system under circumstances where the connector is connected to a SERIO or LANIO system; and detection means operatively connected to with said connector for measuring the level of a signal supplied from said driver means through said connector to a connected system to determine whether the signal meets a predetermined level which is interpretable to differentiate between a connected serial input-output system and a connected local area network input-output system.
Claim 2
Dependent Claim
130 words
Apparatus capable of differentiating between a connected serial input-output (SERIO) system and a connected local area network input-output (LANIO) system, said apparatus comprising: an input-output connector adapted for connection selectively to such a SERIO or LANIO system; driver means operatively connected to said connector for supplying a signal to the connector and by way of said connector to a connected system under circumstances where the connector is connected to a SERIO or LANIO system; and detection means operatively connected to with said connector for measuring the level of a signal supplied from said driver means through said connector to a connected system to determine whether the signal meets a predetermined level which is interpretable to differentiate between a connected serial input-output system and a connected local area network input-output system.
Claim 3
Dependent Claim
44 words
The apparatus of claim 1, wherein said detection means includes translator means for identifying a serial input-output system when the signal's level does not meet the predetermined level, and for identifying a local area network system when the signal's level meets the predetermined level.
Claim 4
Dependent Claim
41 words
The apparatus of claim 1, wherein the signal is electric current, and said detection means includes a current limit resistor through which such current flows and a differential amplifier operatively connected to said resistor to measure the current through the resistor.
Claim 5
Dependent Claim
39 words
The apparatus of claim 3, wherein said differential amplifier produces an output signal, and said detection means further includes a comparator that compares the output signal of the differential amplifier with a predetermined level to produce a comparator voltage.
Claim 6
Dependent Claim
25 words
The apparatus of claim 4, wherein said detection means includes a translator that converts the comparator voltage alternatively into high and low transistor-transistor logic levels.
Claim 7
Dependent Claim
33 words
The apparatus of claim 5, wherein said translator identifies a serial input-output system when the logic level is low, and identifies a local area network input-output system when the logic level is high.
Claim 8
Dependent Claim
116 words
A printer capable of differentiating between a connected serial input-output (SERIO) system and a connected local area network input-output (LANIO) system, said printer comprising: an input-output connector on the printer adapted for connection selectively to such a SERIO or LANIO system; an input-output driver operatively connected to said connector and capable of supplying current in different levels to said connector and by way of said connector to a connected SERIO or LANIO system; detection means operatively connected to said driver for detecting the level of current therefrom supplied through said connector to a connected system; and comparator means operatively connected to said detection means for comparing the level of any detected current with a predetermined level.
Claim 9
Dependent Claim
116 words
A printer capable of differentiating between a connected serial input-output (SERIO) system and a connected local area network input-output (LANIO) system, said printer comprising: an input-output connector on the printer adapted for connection selectively to such a SERIO or LANIO system; an input-output driver operatively connected to said connector and capable of supplying current in different levels to said connector and by way of said connector to a connected SERIO or LANIO system; detection means operatively connected to said driver for detecting the level of current therefrom supplied through said connector to a connected system; and comparator means operatively connected to said detection means for comparing the level of any detected current with a predetermined level.
Claim 10
Dependent Claim
45 words
The printer of claim 7, further comprising translator means for causing the printer to identify a serial input-output system when the current's level does not meet the predetermined level, and to identify a local area network system when the current's level meets the predetermined level.
Claim 11
Independent Claim
102 words
A method whereby a device having an input-output connector and an operatively connected input-output driver capable of supplying current to the connector may differentiate between a connected serial input-output system and a connected local area network input-output system, said method comprising: enabling the input-output driver and thereby supplying current to the connector, and by way of said connector to a connected system; measuring current supplied from the driver to and through the connector; and determining whether the supplied current is of a predetermined level, and if not, identifying a serial input-output system, but if so, identifying a local area network input-output system.
Claim 12
Independent Claim
102 words
A method whereby a device having an input-output connector and an operatively connected input-output driver capable of supplying current to the connector may differentiate between a connected serial input-output system and a connected local area network input-output system, said method comprising: enabling the input-output driver and thereby supplying current to the connector, and by way of said connector to a connected system; measuring current supplied from the driver to and through the connector; and determining whether the supplied current is of a predetermined level, and if not, identifying a serial input-output system, but if so, identifying a local area network input-output system.
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USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1995-06-09 | 1995-12-09 | 1996-06-09 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1999-06-09 | 1999-12-09 | 2000-06-09 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2003-06-09 | 2003-12-09 | 2004-06-09 | $7700.00 | Window Closed / Lapsed |