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US4291386A Expired / Lapsed US ⏱️ 0.0 years remaining

Pseudorandom number generator

Assignee: Unisys Corp
•
Filing: 1980-02-04
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Granted: 1981-09-22
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Expires: 2000-02-04
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Abstract

Abstract An apparatus for testing digital logic circuits without a computer and associated software employs a psuedorandom stream of input data to produce an unstructured output data stream which is analyzed by an efficient data collector and analyzer. Test signal generation is implemented by a pseudorandom number generator and a pseudorandom clock/reset generator while the resulting test data at the output terminals of the device under test is analyzed by a cycle redundancy code checker. Fault localization is realized, with selectable localization and manual probe modes and circuitry is provided for an efficient self-test mode.

Inventors

  • 👤 David S. Bass

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-10-24 05:18
CPC Classifications
G; G01; G01R; G01R31/00; G01R31/28; G01R31/317; G01R31/3181; G01R31/31813; G01R31/319; G01R31/31917; G01R31/31919; G01R31/31921; G06; G06F; G06F11/00; G06F11/22; G06F11/26; G06F11/273; G06F11/277

Claims Analysis

Total Claims: 2
Claim 1
Independent Claim 164 words
A pseudorandom number generator comprising: shift register means having tap means at each stage thereof, data input means and clock input means; K bit modulo two adder means coupled at input means thereof to K selected tap means of said shift register means and at output means thereof to said data input means of said shift register means; register means with each stage thereof coupled correspondingly to said tap means of said shift register means, said register means having tap means at each stage thereof and clock input means; and means coupled between said clock input means of said shift register means and said clock input means of said register means for providing a clock pulse to said clock input means after a preselected number of clock pulses have been applied to said clock input means of said shift register means whereby after each clock pulse applied to said register means a data code is available at said tap means of said register means.
Claim 2
Dependent Claim 164 words
A pseudorandom number generator comprising: shift register means having tap means at each stage thereof, data input means and clock input means; K bit modulo two adder means coupled at input means thereof to K selected tap means of said shift register means and at output means thereof to said data input means of said shift register means; register means with each stage thereof coupled correspondingly to said tap means of said shift register means, said register means having tap means at each stage thereof and clock input means; and means coupled between said clock input means of said shift register means and said clock input means of said register means for providing a clock pulse to said clock input means after a preselected number of clock pulses have been applied to said clock input means of said shift register means whereby after each clock pulse applied to said register means a data code is available at said tap means of said register means.

References Cited (Backward Citations)

US3920894A Cited
US3986168A Cited
US4202051A Cited

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1984-09-21 1985-03-23 1985-09-22 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 1988-09-21 1989-03-23 1989-09-22 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 1992-09-21 1993-03-23 1993-09-22 $7700.00 Window Closed / Lapsed

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