US3935563A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Computer footprint file
Assignee: United States Department of the Navy
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Filing: 1975-01-24
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Granted: 1976-01-27
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Expires: 1995-01-24
Abstract
Abstract Apparatus for keeping track of the progress of a computer program by seleng specific operand and/or instruction references, comprising means for accessing an operand and an instruction reference. Means are connected to a memory data register of the computer and to the two accessing means for selecting one of a specific operand or instruction reference which is to be monitored. A random-access memory (RAM), has three inputs, including one from a memory address and one comprising the output from the selecting means for writing into the RAM the last N instruction and/or operand references, or any combination thereof. A circle counter has an input comprising the named output from the selecting means, for cycling the N references. Means are connected to the circle counter and to the RAM for replacing the oldest reference in the RAM by a new reference from the circle counter, that is, for updating the RAM. Means are connected to the updating means for reading out a specific instruction and/or operand reference.
Inventors
- 👤 Robert A. Unger
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-26 11:16
CPC Classifications
G; G06; G06F; G06F11/00; G06F11/36; G06F11/362; G06F11/3636
Claims Analysis
Total Claims: 5
Claim 1
Independent Claim
164 words
Apparatus for keeping track of the progress of a computer program by selecting specific operand and/or instruction references, comprising: means for accessing an operand reference; means for accessing an instruction reference; means connected to a memory data register of the computer and to the two accessing means for selecting a specific operand or instruction reference which is to be monitored; a random-acess memory (RAM), having three inputs, including one from a memory address and one comprising the output from the selecting means for writing the last N instruction and/or operand references, or any combination thereof into the RAM; a circle counter having an input comprising the same output from the selecting means, for cycling the N references; means connectd to the circle counter and the RAM of replacing the oldest reference in the RAM by a new reference from the circle counter, that is, for updating the RAM; and means connected to the updating means for reading out a specific instruction and/or operand reference.
Claim 2
Dependent Claim
164 words
Apparatus for keeping track of the progress of a computer program by selecting specific operand and/or instruction references, comprising: means for accessing an operand reference; means for accessing an instruction reference; means connected to a memory data register of the computer and to the two accessing means for selecting a specific operand or instruction reference which is to be monitored; a random-acess memory (RAM), having three inputs, including one from a memory address and one comprising the output from the selecting means for writing the last N instruction and/or operand references, or any combination thereof into the RAM; a circle counter having an input comprising the same output from the selecting means, for cycling the N references; means connectd to the circle counter and the RAM of replacing the oldest reference in the RAM by a new reference from the circle counter, that is, for updating the RAM; and means connected to the updating means for reading out a specific instruction and/or operand reference.
Claim 3
Dependent Claim
139 words
The apparatus according to claim 1 wherein the means for selecting a specific reference comprises: an instruction trap control, connected to the memory data register, for trapping an instruction reference; an operand trap control, also connected to the memory data register, for trapping an operand reference; means for setting or clearing the trap controls; a first AND circuit, whose two inputs are connected to the output of the instruction trap control and to an instruction reference from the computer; a second AND circuit, whose two inputs are connected to the output of the operand trap control and to an operand reference from the computer; and an OR circuit, whose two inputs are connected to the outputs of the two AND circuits and whose output comprises one of the inputs to the RAM and the input to the circle counter.
Claim 4
Dependent Claim
79 words
The apparatus according to claim 1 wherein the updating means comprises: an adder, having one input connected to the circle counter and another input connected to the output of the readout means, the adder output constituting a footprint memory address; and a selector circuit, having one input connected to an output of the readout means, and another input connected to the output of the circle counter, the slector providing a means for reading out a selected footprint memory address.
Claim 5
Dependent Claim
79 words
The apparatus according to claim 2, werein the updating means comprises: an adder, having one input connected to the circle counter and another input connected to the output of the readout means, the adder output constituting a footprint memory address; and a selector circuit, having one input connected to an output of the readout means, and another input connected to the output of the circle counter, the selector providing a means for reading out a selected footprint memory address.
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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) | 1979-01-26 | 1979-07-28 | 1980-01-27 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1983-01-26 | 1983-07-28 | 1984-01-27 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1987-01-26 | 1987-07-28 | 1988-01-27 | $7700.00 | Window Closed / Lapsed |