← Back to Patent Explorer
US5243606A Expired / Lapsed US ⏱️ 0.0 years remaining

Apparatus and method for detecting failure of an external device by a microcomputer

Assignee: Mitsubishi Electric Corp
•
Filing: 1989-12-21
•
Granted: 1993-09-07
•
Expires: 2009-12-21
📄 Original PDF 🌐 Google Patents 🔄 Sync Now

Abstract

Abstract The microcomputer of the invention comprises a flip-flop which repeats setting and resetting of a monitor signal. The monitor signal is delivered from an external device in response to a PWM output signal for driving the external device. The flip-flop sets and resets at the front edge, of the monitor signal. The invention detects a failure of the external device according to the presence or absence of inversion of its held value. Hence, the failure of the external device operating at high speeds can be reliably detected by the microcomputer of the invention.

Inventors

  • 👤 Mitsuru Sugita
  • 👤 Kikuo Muramatsu

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-11-03 00:31
CPC Classifications
G; G06; G06F; G06F11/00; G06F11/07; G06F11/0703; G06F11/0751; G05; G05B; G05B9/00; G05B9/02; G06F11/0754; G06F11/0757

Claims Analysis

Total Claims: 15
Claim 1
Independent Claim 123 words
A microcomputer for use in detecting failure in an external device, said external device supplying a state signal in response to a pulse signal, comprising: means for generating a pulse signal for driving said external device; signal holding means for holding a value in response to said state signal supplied from said external device and indicative of the state of said external device, and updating a holding value at every supplying period wherein the value held in said signal holding means changes state in response to a forward edge of said state signal; and failure detecting means for detecting a failure of said external device by comparing the holding value updated by said holding means with the held value updated one period before.
Claim 2
Dependent Claim 123 words
A microcomputer for use in detecting failure in an external device, said external device supplying a state signal in response to a pulse signal, comprising: means for generating a pulse signal for driving said external device; signal holding means for holding a value in response to said state signal supplied from said external device and indicative of the state of said external device, and updating a holding value at every supplying period wherein the value held in said signal holding means changes state in response to a forward edge of said state signal; and failure detecting means for detecting a failure of said external device by comparing the holding value updated by said holding means with the held value updated one period before.
Claim 3
Dependent Claim 22 words
A microcomputer as set forth in claim 1, wherein said signal holding means is comprised of one or plural stages of flip-flops.
Claim 4
Dependent Claim 128 words
A microcomputer for use in detecting failure in an external device, said external device supplying a state signal in response to a pulse signal, comprising: means for generating a pulse signal for driving said external device; signal holding means for holding a value in response to said state signal supplied from said external device and indicative of the state of said external device, and updating a holding value at every supplying period wherein the value held in said signal holding means changes state in response to a forward edge of said state signal; and failure detecting means for detecting a failure of said external device on the basis of the holding value updated by said holding means; and wherein said signal holding means is comprised of a counter.
Claim 5
Dependent Claim 128 words
A microcomputer for use in detecting failure in an external device, said external device supplying a state signal in response to a pulse signal, comprising: means for generating a pulse signal for driving said external device; signal holding means for holding a value in response to said state signal supplied from said external device and indicative of the state of said external device, and updating a holding value at every supplying period wherein the value held in said signal holding means changes state in response to a forward edge of said state signal; and failure detecting means for detecting a failure of said external device on the basis of the holding value updated by said holding means; and wherein said signal holding means is comprised of a counter.
Claim 6
Independent Claim 106 words
A method for detecting failure in an external device, said external device receiving a pulse signal with a plurality of pulses defining a plurality of periods of said pulse signal, said external device supplying a state signal in response to said pulse signal, the state signal having a plurality of edges including at least predetermined type of edge, the method comprising toggling a held signal between two states whenever there is said predetermined type of edge in said state signal; and detecting failure by comparing with held value updated one period before to determine whether said held signal inverts at each period of said pulse signal.
Claim 7
Independent Claim 106 words
A method for detecting failure in an external device, said external device receiving a pulse signal with a plurality of pulses defining a plurality of periods of said pulse signal, said external device supplying a state signal in response to said pulse signal, the state signal having a plurality of edges including at least predetermined type of edge, the method comprising toggling a held signal between two states whenever there is said predetermined type of edge in said state signal; and detecting failure by comparing with held value updated one period before to determine whether said held signal inverts at each period of said pulse signal.
Claim 8
Independent Claim 126 words
A method for detecting failure in an external device, said external device receiving a pulse signal with a plurality of pulses defining a plurality of periods of said pulse signal, said external device supplying a state signal in response to said pulse signal, the state signal having a plurality of edges including at least predetermined type of edge, the method comprising toggling a held signal between two states whenever there is said predetermined type of edge in said state signal; detecting failure by determining whether said held signal inverts at each period of said pulse signal; and wherein said step of detecting includes storing an indication of the value of said held signal and comparing said stored indication to a current value of said held signal.
Claim 9
Independent Claim 126 words
A method for detecting failure in an external device, said external device receiving a pulse signal with a plurality of pulses defining a plurality of periods of said pulse signal, said external device supplying a state signal in response to said pulse signal, the state signal having a plurality of edges including at least predetermined type of edge, the method comprising toggling a held signal between two states whenever there is said predetermined type of edge in said state signal; detecting failure by determining whether said held signal inverts at each period of said pulse signal; and wherein said step of detecting includes storing an indication of the value of said held signal and comparing said stored indication to a current value of said held signal.
Claim 10
Dependent Claim 16 words
A method, as claimed in claim 5, wherein said storing includes storing in a single latch.
Claim 11
Dependent Claim 17 words
A method, as claimed in claim 5, wherein said storing includes storing in at least two latches.
Claim 12
Dependent Claim 146 words
Apparatus for use in a device for detecting failure of an external device, said external device receiving a pulse signal, said external device supplying a state signal in response to said pulse signal, the state signal having a plurality of edges including at least predetermined type of edge, the apparatus comprising: a comparator having an input which determines whether a signal provided at said input is inverted with respect to a previous signal; an edge detector having an input and an output which toggles the level of a signal at its output between first and second levels in response to detecting an edge of said predetermined type in a signal supplied at said input; means for supplying said state signal to said input of said edge detector; and means for supplying the signal from the output of said edge detector to the input of the comparator.
Claim 13
Dependent Claim 146 words
Apparatus for use in a device for detecting failure of an external device, said external device receiving a pulse signal, said external device supplying a state signal in response to said pulse signal, the state signal having a plurality of edges including at least predetermined type of edge, the apparatus comprising: a comparator having an input which determines whether a signal provided at said input is inverted with respect to a previous signal; an edge detector having an input and an output which toggles the level of a signal at its output between first and second levels in response to detecting an edge of said predetermined type in a signal supplied at said input; means for supplying said state signal to said input of said edge detector; and means for supplying the signal from the output of said edge detector to the input of the comparator.
Claim 14
Dependent Claim 145 words
Apparatus for detecting failure of an external device, said external device receiving a pulse signal, said external device supplying a state signal in response to said pulse signal, the state signal having a plurality of rising edges, the apparatus comprising: a pulse signal generator having an output coupled to said external device; a flip-flop having an input and an output which receives said state signal at said input and toggles the level of a held signal at its output between first and second levels in response to a rising edge in said state signal; at least one latch for storing said held signal received from said flip-flop during one period of said pulse signal; logic gates for receiving said stored held signal and a current held signal and outputting a detection signal if said stored held signal is not inverted from said current held signal.
Claim 15
Dependent Claim 145 words
Apparatus for detecting failure of an external device, said external device receiving a pulse signal, said external device supplying a state signal in response to said pulse signal, the state signal having a plurality of rising edges, the apparatus comprising: a pulse signal generator having an output coupled to said external device; a flip-flop having an input and an output which receives said state signal at said input and toggles the level of a held signal at its output between first and second levels in response to a rising edge in said state signal; at least one latch for storing said held signal received from said flip-flop during one period of said pulse signal; logic gates for receiving said stored held signal and a current held signal and outputting a detection signal if said stored held signal is not inverted from said current held signal.

References Cited (Backward Citations)

US3046524A Cited
US3707714A Cited
US3881094A Cited
US4099668A Cited
US4283766A Cited
JPS59133652A Cited
JPS6017545A Cited
US4817418A Cited
US4712213A Cited
US4916698A Cited
US5048017A Cited
US5095483A Cited

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1996-09-06 1997-03-08 1997-09-07 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 2000-09-06 2001-03-08 2001-09-07 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 2004-09-06 2005-03-08 2005-09-07 $7700.00 Window Closed / Lapsed

Assigned Categories & Tags

No categories assigned to this patent yet.

Assign Category Tag