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US4447876A Expired / Lapsed US ⏱️ 0.0 years remaining

Emulator control sequencer

Assignee: Tektronix Inc
•
Filing: 1981-07-30
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Granted: 1984-05-08
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Expires: 2001-07-30
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Abstract

Abstract An emulator control sequencer comprises a programmable state machine which passively monitors the data bus of an emulator microprocessor, extracts certain information indicative of internal processor behavior, such as when the next opcode fetch will occur, as well as detecting current opcodes, and generates control signals for the emulator.

Inventors

  • 👤 Wayne A. Moore

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-10-23 17:25
CPC Classifications
G; G06; G06F; G06F9/00; G06F9/06; G06F9/30; G06F9/3017; G06F9/30174; G06F9/38; G06F9/3877; G06F9/3879

Claims Analysis

Total Claims: 10
Claim 1
Independent Claim 169 words
An emulator control sequencer for monitoring an emulator processor data bus, decoding instructions predictive of emulator processor behavior passing thereover from a system processor to said emulator processor, and generating control signals for said emulator processor, comprising: first decoding means for decoding bytes of instruction data occuring on said data bus to provide instruction-type data words; a state machine comprising storage means containing a set of instructions in addressable storage locations therein and being responsive to said instruction-type data words to execute said instructions and produce a plurality of control data thereby, and address generator means responsive to at least a portion of said plurality of control data for addressing storage locations of said storage means in a predetermined sequence determinable by said instruction-type data words, said state machine receiving an emulator processor clock signal and operating in synchromism therewith; and second decoding means for decoding at least a portion of said plurality of control data thereby to produce said control signals in response to emulator processor status signals.
Claim 2
Dependent Claim 169 words
An emulator control sequencer for monitoring an emulator processor data bus, decoding instructions predictive of emulator processor behavior passing thereover from a system processor to said emulator processor, and generating control signals for said emulator processor, comprising: first decoding means for decoding bytes of instruction data occuring on said data bus to provide instruction-type data words; a state machine comprising storage means containing a set of instructions in addressable storage locations therein and being responsive to said instruction-type data words to execute said instructions and produce a plurality of control data thereby, and address generator means responsive to at least a portion of said plurality of control data for addressing storage locations of said storage means in a predetermined sequence determinable by said instruction-type data words, said state machine receiving an emulator processor clock signal and operating in synchromism therewith; and second decoding means for decoding at least a portion of said plurality of control data thereby to produce said control signals in response to emulator processor status signals.
Claim 3
Dependent Claim 45 words
An emulator control sequencer in accordance with claim 1 wherein said first decoding means comprises a first random-access memory containing predetermined instruction-type data words at addressable storage locations therein, said random-access memory being addressed by said bytes of instruction data occuring on said data bus.
Claim 4
Dependent Claim 37 words
An emulator control sequencer in accordance with claim 2 wherein said first decoding means further comprises a latch for receiving and storing said instruction-type data words from said random-access memory upon receipt of a predetermined clock signal.
Claim 5
Dependent Claim 38 words
An emulator control sequencer in accordance with claim 3 wherein said instruction-type data words are coupled from said latch to address additional addressable storage locations of said first random-access memory thereby to provide further decoded instruction-type data words.
Claim 6
Dependent Claim 16 words
An emulator control sequencer in accordance with claim 3 wherein said first random-access memory is programmable.
Claim 7
Dependent Claim 39 words
An emulator control sequencer in accordance with claim 2 wherein said first random-access memory also contains predetermined branch addresses stored therein so that said first decoding means also produces branch addresses to be applied to said address generator means.
Claim 8
Dependent Claim 28 words
An emulator control sequencer in accordance with claim 2 wherein said storage means of said state machine comprises a second random-access memory, said second random-access memory being programmable.
Claim 9
Dependent Claim 49 words
An emulator control sequencer in accordance with claim 1 wherein said state machine further comprises register means coupled between the output of said storage means and the input of said address generator means, said register means and said address generator means being operable in synchronism with said clock signal.
Claim 10
Dependent Claim 53 words
An emulator control sequencer in accordance with claim 1 wherein said first decoding means also produces branch addresses and said storage means of said state machine also produces branch addresses, and said address generator means is further selectively responsive to branch addresses from one of said first decoding means and said storage means.

References Cited (Backward Citations)

US4050058A Cited
US4210960A Cited
US4249248A Cited

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1987-05-08 1987-11-07 1988-05-08 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 1991-05-08 1991-11-07 1992-05-08 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 1995-05-08 1995-11-07 1996-05-08 $7700.00 Window Closed / Lapsed

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