US4597052A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Digital control system with error monitor operative upon starting system operation
Assignee: Nissan Motor Co Ltd
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Filing: 1984-05-14
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Granted: 1986-06-24
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Expires: 2004-05-14
Abstract
Abstract A digital control system is provided with an error monitor system which applies dummy loads to an actuator and a monitor lamp in order to check the operation thereof. The digital control system also has a watch-dog timer responsive to a periodic signal produced as long as a microprocessor of the control system is operating normally. The control system is adapted to be initialized in response to the onset of power supply and in response to error signals from the watch-dog timer. A discriminator is provided in the control system to discriminate the cause of initialization of the control system. The discriminator enables the error monitor system when initialization due to onset of power supply is detected but not when initialization is due to errors detected by the watch-dog timer.
Inventors
- 👤 Toshiro Matsuda
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-26 05:26
CPC Classifications
G; G06; G06F; G06F11/00; G06F11/07; G06F11/0703; G06F11/0706; G06F11/0736; G06F11/0739; G05; G05B; G05B19/00; G05B19/02; G05B19/04; G05B19/042; G05B19/0428; G06F11/0751; G06F11/14; G06F11/1402; G06F11/1415; G06F11/1417
Claims Analysis
Total Claims: 12
Claim 1
Independent Claim
119 words
A digital control system including a microprocessor which among other functions, checks an actuator to be controlled by the system and an operation monitor, comprising: first means for resetting and initializing the control system; second means for activating said first means in response to the onset of power supply to the control system; third means for detecting malfunction of said control system and activating said first means when malfunction of the control system is detected; fourth means, responsive to said first means being activated for applying a dummy load to said actuator and said operation monitor for testing the latter; and fifth means, responsive to activation of said first means by said third means for disabling said fourth means.
Claim 2
Dependent Claim
119 words
A digital control system including a microprocessor which among other functions, checks an actuator to be controlled by the system and an operation monitor, comprising: first means for resetting and initializing the control system; second means for activating said first means in response to the onset of power supply to the control system; third means for detecting malfunction of said control system and activating said first means when malfunction of the control system is detected; fourth means, responsive to said first means being activated for applying a dummy load to said actuator and said operation monitor for testing the latter; and fifth means, responsive to activation of said first means by said third means for disabling said fourth means.
Claim 3
Dependent Claim
37 words
The digital control system as set forth in claim 1, wherein said fifth means is responsive to the onset of power supply to said control system for enabling said fourth means for a predetermined period of time.
Claim 4
Dependent Claim
32 words
The digital control system as set forth in claim 2, wherein said second means is active for a given period of time after the onset of power supply to the control system.
Claim 5
Dependent Claim
40 words
The digital control system as set forth in claim 3, wherein said predetermined period of time during which said fifth means enables said fourth means is longer than said given period of time for which said second means is active.
Claim 6
Dependent Claim
163 words
An error monitor system for a digital control system controlling an automotive vehicle device, comprising: a microprocessor performing control operations for the automotive device in accordance with a preselected control parameter, said microprocessor producing periodic signals having a period shorter than a predetermined period as long as the microprocessor is operating normally; a first detector for measuring the period of said periodic signal and producing a first detector signal when the measured period exceeds said predetermined period; a second detector for detecting power supply to said microprocessor and outputting a second detector signal for a predetermined period of time in response to the onset of power supply; means for resetting the control system in response to either of said first and second detector signals and initializing the control system; and means for applying a dummy load signal to devices to be controlled by the control system, said dummy load applying means being responsive to said second detector signal to produce said dummy signal.
Claim 7
Dependent Claim
163 words
An error monitor system for a digital control system controlling an automotive vehicle device, comprising: a microprocessor performing control operations for the automotive device in accordance with a preselected control parameter, said microprocessor producing periodic signals having a period shorter than a predetermined period as long as the microprocessor is operating normally; a first detector for measuring the period of said periodic signal and producing a first detector signal when the measured period exceeds said predetermined period; a second detector for detecting power supply to said microprocessor and outputting a second detector signal for a predetermined period of time in response to the onset of power supply; means for resetting the control system in response to either of said first and second detector signals and initializing the control system; and means for applying a dummy load signal to devices to be controlled by the control system, said dummy load applying means being responsive to said second detector signal to produce said dummy signal.
Claim 8
Dependent Claim
49 words
The error monitor system as set forth in claim 5, which further comprises means responsive to the onset of power supply to said control system for enabling said dummy load applying means for a given period of time and for disabling the latter after said given period of time.
Claim 9
Dependent Claim
39 words
The error monitor system as set forth in claim 6, wherein said given period of time for which said dummy load applying means in enabled is longer than said predetermined period for which said second detector signal is output.
Claim 10
Dependent Claim
33 words
The error monitor system as set forth in claim 7, wherein said dummy load applying means is active only when said second detector signal is input while it is in an enabled state.
Claim 11
Dependent Claim
18 words
The error monitor system as set forth in claim 8, wherein said first detector comprises a watchdog timer.
Claim 12
Dependent Claim
31 words
The error monitor system as set forth in claim 9, wherein said resetting means is active in response to the trailing edge of either of said first and second detector signals.
References Cited (Backward Citations)
US3972230A
Cited
US4306218A
Cited
US4267569A
Cited
US4287565A
Cited
US4363092A
Cited
US4338670A
Cited
US4376298A
Cited
US4399537A
Cited
US4480303A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1989-06-23 | 1989-12-23 | 1990-06-24 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1993-06-23 | 1993-12-23 | 1994-06-24 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1997-06-23 | 1997-12-23 | 1998-06-24 | $7700.00 | Window Closed / Lapsed |