US3594656A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Automatic clock frequency-switching system
Assignee: National Institute of Advanced Industrial Science and Technology
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Filing: 1970-03-24
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Granted: 1971-07-20
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Expires: 1990-03-24
Abstract
Abstract An automatic clock frequency-switching system for electric systems such as electronic computer systems comprising a clock source including a plurality of oscillators generating frequencies different from one another, and a clock frequency control capable of performing a stable operation even during the period when clock is interrupted. While the clock frequency is being switched, the supply of clock to a mechanism which is operative in response to clock pulses is stopped. After the clock frequency has been switched clock is supplied to the mechanism to resume the operation thereof.
Inventors
- 👤 Yoshihiro Tsukamoto
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-26 10:18
CPC Classifications
G; G06; G06F; G06F1/00; G06F1/04; G06F1/08
Claims Analysis
Total Claims: 10
Claim 1
Independent Claim
185 words
A system for switching clock frequencies comprising: a. a general logic part including a main control, said main control being operative in response to clock pulses for generating frequency selection information and a frequencyswitching request signal at the time of frequency switching, b. a clock frequency control for generating a clock stop signal and a frequency-switching signal upon receipt of said frequency-switching request signal from said main control and supplying a frequency-switching end signal to said main control after the end of frequency-switching operation. c. a clock source including a plurality of oscillators of oscillation frequencies different from one another, d. a frequency selector for selecting one of said oscillators by the reception of said frequency selection information from said main control and said frequency-switching request signal from said clock frequency control. e. a clock generator connected to said frequency selector for generating at least fundamental clock pulses, and f. a clock gate for gating said clock pulses from said clock generator in response to said clock stop signal from said clock frequency control and supplying said clock pulses to at least said main control.
Claim 2
Independent Claim
185 words
A system for switching clock frequencies comprising: a. a general logic part including a main control, said main control being operative in response to clock pulses for generating frequency selection information and a frequencyswitching request signal at the time of frequency switching, b. a clock frequency control for generating a clock stop signal and a frequency-switching signal upon receipt of said frequency-switching request signal from said main control and supplying a frequency-switching end signal to said main control after the end of frequency-switching operation. c. a clock source including a plurality of oscillators of oscillation frequencies different from one another, d. a frequency selector for selecting one of said oscillators by the reception of said frequency selection information from said main control and said frequency-switching request signal from said clock frequency control. e. a clock generator connected to said frequency selector for generating at least fundamental clock pulses, and f. a clock gate for gating said clock pulses from said clock generator in response to said clock stop signal from said clock frequency control and supplying said clock pulses to at least said main control.
Claim 3
Dependent Claim
34 words
A system for switching clock frequencies according to claim 1, wherein said main control is operative to generate frequency selection information and a frequency-switching request signal at the operation stage of a frequency-switching instruction.
Claim 4
Dependent Claim
24 words
A system for switching clock frequencies according to claim 1, wherein said clock frequency control performs its operation nonsynchronously with said general logic part.
Claim 5
Dependent Claim
55 words
A system for switching clock frequencies according to claim 1, wherein said general logic part is such that during the continuation of the operation stage of a frequency-switching instruction, the transfer of information and control signals does not occur between said general logic part and and apparatus which operates nonsynchronously with said general logic part.
Claim 6
Dependent Claim
24 words
A system for switching clock frequencies according to claim 1, wherein said oscillation frequencies of said oscillators in said clock source are fixed frequencies.
Claim 7
Dependent Claim
30 words
A system for switching clock frequencies according to claim 1, wherein each of said oscillators in said clock source is finely adjustable in its oscillation frequency around its proper frequency.
Claim 8
Dependent Claim
50 words
A system for switching clock frequencies according to claim 1, wherein said clock generator generates an output clock signal in response to an input clock signal, the frequencies of said input and output clock signals having a relation of n to 1 (n is a positive integer including 1) therebetween.
Claim 9
Dependent Claim
60 words
A system for switching clock frequencies according to claim 1, wherein said clock gate is actuated by synchronizing the signal from said clock frequency control with clock to be gated supplied from said clock generator, whereby said clock gate is prevented from malfunctioning resulting from disturbance of the output of said clock generator at the time of clock frequency switching.
Claim 10
Dependent Claim
35 words
A system for switching clock frequencies according to claim 1, wherein said frequency control performs a control such that said frequency selector switches the frequency after said clock gate stops the supply of clock pulses.
References Cited (Backward Citations)
No citation records indexed.
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1974-07-19 | 1975-01-18 | 1975-07-20 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1978-07-19 | 1979-01-18 | 1979-07-20 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1982-07-19 | 1983-01-18 | 1983-07-20 | $7700.00 | Window Closed / Lapsed |