US4363092A
Expired / Lapsed
US
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Malfunction preventing system for a microcomputer system
Assignee: Nissan Motor Co Ltd
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Filing: 1979-09-12
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Granted: 1982-12-07
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Expires: 1999-09-12
Abstract
Abstract A malfunction preventing system for a microcomputer system is disclosed which detects an abnormal condition in the program execution to produce an alarm or reset signal to automatically restart the computer. The malfunction preventing system is applicable to automotive engine control wherein the computer is capable of returning to normal operation upon detecting a malfunction in program operation for fuel parameter calculation, thereby to keep the automotive engine control in order.
Inventors
- 👤 Toshimi Abo
- 👤 Akio Hosaka
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-25 18:22
CPC Classifications
G; G06; G06F; G06F11/00; G06F11/07; G06F11/0703; G06F11/0751; G06F11/0754; G06F11/0757; F; F02; F02D; F02D41/00; F02D41/24; F02D41/26; F02D41/263; F02D41/266
Claims Analysis
Total Claims: 18
Claim 1
Independent Claim
276 words
Apparatus for preventing certain malfunctions of a microcomputer that is normally periodically cycled through a program, the microcomputer including a reset and initialization input terminal, the apparatus comprising a reset circuit for normally applying a first voltage to the reset and initialization input terminal, the microcomputer responding to the first voltage at the reset and initialization input terminal to continuously recycle the program, means responsive to power being initially applied to the microcomputer and the reset circuit for activating the reset circuit so the reset circuit applies a second voltage to the reset input for a predetermined interval after power is initially applied to the microcomputer and reset circuit, the microcomputer responding to the second voltage to reset the program to a starting point and initialize parameters associated with the program, the predetermined interval being greater than a predetermined time required for the microcomputer to execute a program cycle plus the time required to reset and initialize the microcomputer, the microcomputer deriving a program run impulse in response to the microcomputer executing each program cycle, whereby the microcomputer while normally operating derives adjacent periodic program run impulses at intervals spaced from each other by a predetermined time, the predetermined time being less than the predetermined interval, and means connected to the microcomputer to be responsive to the program run impulses for supplying the second voltage to the reset and initialization input terminal in response to a pair of the impulses not occurring in a predetermined duration, the predetermined duration being greater than the predetermined time, whereby the program is immediately reset and initialized in response to the microcomputer not executing the program within the predetermined duration.
Claim 2
Dependent Claim
276 words
Apparatus for preventing certain malfunctions of a microcomputer that is normally periodically cycled through a program, the microcomputer including a reset and initialization input terminal, the apparatus comprising a reset circuit for normally applying a first voltage to the reset and initialization input terminal, the microcomputer responding to the first voltage at the reset and initialization input terminal to continuously recycle the program, means responsive to power being initially applied to the microcomputer and the reset circuit for activating the reset circuit so the reset circuit applies a second voltage to the reset input for a predetermined interval after power is initially applied to the microcomputer and reset circuit, the microcomputer responding to the second voltage to reset the program to a starting point and initialize parameters associated with the program, the predetermined interval being greater than a predetermined time required for the microcomputer to execute a program cycle plus the time required to reset and initialize the microcomputer, the microcomputer deriving a program run impulse in response to the microcomputer executing each program cycle, whereby the microcomputer while normally operating derives adjacent periodic program run impulses at intervals spaced from each other by a predetermined time, the predetermined time being less than the predetermined interval, and means connected to the microcomputer to be responsive to the program run impulses for supplying the second voltage to the reset and initialization input terminal in response to a pair of the impulses not occurring in a predetermined duration, the predetermined duration being greater than the predetermined time, whereby the program is immediately reset and initialized in response to the microcomputer not executing the program within the predetermined duration.
Claim 3
Dependent Claim
172 words
In combination, a microcomputer for normally periodically executing a program, said microcomputer including an output means for generating an output signal in response to the microcomputer executing the program, the output signal having a predetermined periodically occurring characteristic only while the microcomputer normally periodically executes the program; apparatus for preventing certain malfunctions of the microcomputer, said apparatus comprising: first means connected to the output means to respond to said output signal for indicating an abnormal condition of the microcomputer in response to the predetermined periodic characteristic not occurring for a time interval in excess of a predetermined interval greater than the period of the predetermined periodic characteristic; second means connected to the first means to respond to the abnormal condition being indicated for periodically resetting the program while the abnormal condition is indicated by the first means; and third means connected to respond to the second means for deriving an alarm signal in response to the program being repeatedly reset by the second means at a frequency exceeding a predetermined occurrence frequency.
Claim 4
Dependent Claim
172 words
In combination, a microcomputer for normally periodically executing a program, said microcomputer including an output means for generating an output signal in response to the microcomputer executing the program, the output signal having a predetermined periodically occurring characteristic only while the microcomputer normally periodically executes the program; apparatus for preventing certain malfunctions of the microcomputer, said apparatus comprising: first means connected to the output means to respond to said output signal for indicating an abnormal condition of the microcomputer in response to the predetermined periodic characteristic not occurring for a time interval in excess of a predetermined interval greater than the period of the predetermined periodic characteristic; second means connected to the first means to respond to the abnormal condition being indicated for periodically resetting the program while the abnormal condition is indicated by the first means; and third means connected to respond to the second means for deriving an alarm signal in response to the program being repeatedly reset by the second means at a frequency exceeding a predetermined occurrence frequency.
Claim 5
Dependent Claim
235 words
In combination, a microcomputer, said microcomputer including an output means for detecting a normal operating condition of the microcomputer, said output means normally producing an output signal with a predetermined periodic characteristic while the microcomputer operates in the normal condition and discontinuing derivation of said output signal in response to the microcomputer failing to operate in the normal condition, apparatus for preventing certain malfunctions of the microcomputer, said apparatus comprising: first means connected to said output means for detecting said output signal of said output means and for indicating a failure of the normal microcomputer operation in response to said output signal not being derived by the output means and detected by the first means for a time interval longer than the time between adjacent occurrences of the predetermined periodic characteristic of said output, second means responsive for periodically resetting the microcomputer to an operating point in the normal operating condition in response to the first means indicating the failure, third means for counting occurrence of said second means resetting the microcomputer to derive a counted value signal, means for comparing a value indicated by the counted value signal with a predetermined value for producing an alarm signal in response to the value associated with the counted value being larger than said predetermined value; and a warning system responsive to the alarm signal for deriving an indication of failure of normal operation of the microcomputer.
Claim 6
Dependent Claim
235 words
In combination, a microcomputer, said microcomputer including an output means for detecting a normal operating condition of the microcomputer, said output means normally producing an output signal with a predetermined periodic characteristic while the microcomputer operates in the normal condition and discontinuing derivation of said output signal in response to the microcomputer failing to operate in the normal condition, apparatus for preventing certain malfunctions of the microcomputer, said apparatus comprising: first means connected to said output means for detecting said output signal of said output means and for indicating a failure of the normal microcomputer operation in response to said output signal not being derived by the output means and detected by the first means for a time interval longer than the time between adjacent occurrences of the predetermined periodic characteristic of said output, second means responsive for periodically resetting the microcomputer to an operating point in the normal operating condition in response to the first means indicating the failure, third means for counting occurrence of said second means resetting the microcomputer to derive a counted value signal, means for comparing a value indicated by the counted value signal with a predetermined value for producing an alarm signal in response to the value associated with the counted value being larger than said predetermined value; and a warning system responsive to the alarm signal for deriving an indication of failure of normal operation of the microcomputer.
Claim 7
Dependent Claim
93 words
The combination of claim 2 or 3, wherein said first means comprises: a capacitor, means for charging the capacitor with a predetermined time constant between adjacent occurrences of the output signal, means for discharging the capacitor in response to said output signal, and means for sensing the voltage across the capacitor for indicating the microcomputer abnormal condition in response to the voltage across the capacitor exceeding a predetermined level associated with: (a) the time constant, (b) a charging voltage for the capacitor and (c) the time between adjacent occurrences of the output signal.
Claim 8
Dependent Claim
56 words
The combination of claim 2 or 3 wherein a portion of the program includes a routine that is cyclically executed in response to the microcomputer normally periodically executing the program, said routine commanding said output means of said microcomputer to derive a pulse signal, said pulse signal being said output signal with the predetermined periodic characteristic.
Claim 9
Dependent Claim
25 words
The combination of claim 3, wherein said program includes an interrupt routine, said microcomputer deriving said pulse signal after confirming execution of the interrupt routine.
Claim 10
Dependent Claim
34 words
The combination of claim 2 or 3, wherein said microcomputer includes a memory, and means for deriving a read/write signal for controlling the memory, said pulse signal being a read/write signal of the microcomputer.
Claim 11
Dependent Claim
16 words
The combination of claim 2 or 3, wherein said first means comprises a retriggerable monostable multivibrator.
Claim 12
Dependent Claim
42 words
The combination of claim 2 or 3 wherein said microcomputer includes a reset input and said second means includes means responsive to the indication of abnormality for deriving a reset signal that is coupled to the reset input of the microcomputer system.
Claim 13
Dependent Claim
27 words
The combination of claim 9 further including a real time device, the microcomputer including an output port for supplying a control signal to the real time device.
Claim 14
Dependent Claim
189 words
In combination, a microcomputer including means for deriving a program run signal in response to each execution of a normally periodically recurring program of the microcomputer; apparatus for preventing certain malfunctions of the microcomputer, said apparatus comprising: first means responsive to the program run signal for indicating that the program run signal is not being derived for a predetermined time interval in excess of the period between adjacent occurrences of the program run signal while the program normally recurs, said first means including: a capacitor, means for charging the capacitor with a predetermined time constant between adjacent occurrences of the program run signal, means for discharging the capacitor in response to said program run signal, and means for sensing the voltage across the capacitor for deriving said indication in response to the voltage across the capacitor exceeding a predetermined level associated with: (1) the time constant, (2) a charging voltage for the capacitor, and (3) the time between program run signals while the program normally recurs; second means responsive to said first means for periodically resetting the microcomputer program to a starting point while the indication is being derived;
Claim 15
Dependent Claim
189 words
In combination, a microcomputer including means for deriving a program run signal in response to each execution of a normally periodically recurring program of the microcomputer; apparatus for preventing certain malfunctions of the microcomputer, said apparatus comprising: first means responsive to the program run signal for indicating that the program run signal is not being derived for a predetermined time interval in excess of the period between adjacent occurrences of the program run signal while the program normally recurs, said first means including: a capacitor, means for charging the capacitor with a predetermined time constant between adjacent occurrences of the program run signal, means for discharging the capacitor in response to said program run signal, and means for sensing the voltage across the capacitor for deriving said indication in response to the voltage across the capacitor exceeding a predetermined level associated with: (1) the time constant, (2) a charging voltage for the capacitor, and (3) the time between program run signals while the program normally recurs; second means responsive to said first means for periodically resetting the microcomputer program to a starting point while the indication is being derived;
Claim 16
Dependent Claim
42 words
third means responsive to the second means for counting the number of times the second means resets the computer; and means responsive to the third means for deriving an alarm signal in response to the counted value being above a predetermined value.
Claim 17
Dependent Claim
42 words
third means responsive to the second means for counting the number of times the second means resets the computer; and means responsive to the third means for deriving an alarm signal in response to the counted value being above a predetermined value.
Claim 18
Dependent Claim
32 words
The combination of claim 2, 3 or 4, wherein said program includes instructions for controlling fuel supply for an automotive engine based on operating parameters for a controller of the automotive engine.
References Cited (Backward Citations)
US4097924A
Cited
US4204249A
Cited
US4145739A
Cited
DE2845350A1
Cited
US4255789A
Cited
US4162526A
Cited
US4231091A
Cited
US4236213A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1985-12-06 | 1986-06-07 | 1986-12-07 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1989-12-06 | 1990-06-07 | 1990-12-07 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1993-12-06 | 1994-06-07 | 1994-12-07 | $7700.00 | Window Closed / Lapsed |