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US4298978A Expired / Lapsed US ⏱️ 0.0 years remaining

Data communication apparatus

Assignee: Ricoh Co Ltd
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Filing: 1980-02-26
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Granted: 1981-11-03
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Expires: 2000-02-26
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Abstract

Abstract A group of address signals is constituted by a start bit followed by a predetermined number of address bits and a stop bit. A group of data signals preceding another group of data signals is constituted by a start bit followed by the same predetermined number of data bits and a stop bit. A group of data signals preceding a group of address signals is constituted by a start bit followed by the predetermined number of data bits and two stop bits. At the receiving end, as a group of signals is received, a bit corresponding to the predetermined number plus three is sensed. If the sensed bit is a start bit, the next group is processed as a group of data signals. If the sensed bit is a stop bit, the next group is processed as a group of address signals.

Inventors

  • 👤 Haruka Nakamura

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-10-24 20:07
CPC Classifications
H; H04; H04L; H04L12/00; H04L12/28; H04L12/40; H04L12/40006; H04L12/40013; G; G06; G06F; G06F13/00; G06F13/38; G06F13/42; G06F13/4204; G06F13/4208; G06F13/4213; H04L12/403; H04Q; H04Q9/00; H04Q9/14

Claims Analysis

Total Claims: 7
Claim 1
Independent Claim 162 words
A data communication apparatus comprising: transmission means for selectively transmitting groups of address signals and groups of data signals, each group of address signals comprising a start bit, a predetermined number of address bits and a stop bit, each group of data signals preceding another group of data signals comprising a start bit, said predetermined number of data bits and a stop bit, each group of data signals preceding a group of address signals comprising a start bit, said predetermined number of data bits and two stop bits; and reception means for receiving groups of signals, the reception means comprising sensor means for sensing, in a group of signals, a bit following said predetermined number of bits plus two bits and processing a next group of signals as a group of address signals when said sensed bit is a stop bit and processing a next group of signals as a group of data signals when said sensed bit is a start bit.
Claim 2
Dependent Claim 162 words
A data communication apparatus comprising: transmission means for selectively transmitting groups of address signals and groups of data signals, each group of address signals comprising a start bit, a predetermined number of address bits and a stop bit, each group of data signals preceding another group of data signals comprising a start bit, said predetermined number of data bits and a stop bit, each group of data signals preceding a group of address signals comprising a start bit, said predetermined number of data bits and two stop bits; and reception means for receiving groups of signals, the reception means comprising sensor means for sensing, in a group of signals, a bit following said predetermined number of bits plus two bits and processing a next group of signals as a group of address signals when said sensed bit is a stop bit and processing a next group of signals as a group of data signals when said sensed bit is a start bit.
Claim 3
Dependent Claim 40 words
An apparatus as in claim 1, in which the sensor means comprises timer means for generating a sample signal at a time corresponding to said sensed bit, the sensor means sensing said sensed bit in response to the sample signal.
Claim 4
Dependent Claim 28 words
An apparatus as in claim 2, in which the timer means comprises clock pulse generator means for generating clock pulses and counter means for counting the clock pulses.
Claim 5
Dependent Claim 24 words
An apparatus as in claim 3, in which the sample signal is constituted by a high order stage output signal of the counter means.
Claim 6
Dependent Claim 36 words
An apparatus as in claim 2, in which the sensor means comprises a D-type flip-flop having a D input connected to receive the groups of signals and a clock input connected to receive the sample signal.
Claim 7
Dependent Claim 87 words
An apparatus as in claim 3, in which the counter means comprises a counter for counting the clock pulses, an AND gate having an input connected to receive the clock pulses and an output connected to a clock input of the counter, the counter means further comprising a flip-flop having an output connected to an input of the AND gate, the flip-flop being set by a start bit to enable the AND gate and reset by an overflow signal of the counter to inhibit the AND gate.

References Cited (Backward Citations)

US3207851A Cited
US3396239A Cited
US4071706A Cited
US4168400A Cited

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1984-11-02 1985-05-04 1985-11-03 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 1988-11-02 1989-05-04 1989-11-03 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 1992-11-02 1993-05-04 1993-11-03 $7700.00 Window Closed / Lapsed

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