On-vehicle electronic control device
First Claim
1. An on-vehicle electronic control device, comprising:
- a nonvolatile program memory for storing a control program and a control constant;
a microprocessor which is connected to a first serial-parallel converter via a bus and which executes the control program;
a concurrent control circuit which is serially connected to the microprocessor via a second serial-parallel converter, wherein the microprocessor and the concurrent control circuit function in cooperation to control an on-vehicle electric load group based on input signals from an on-vehicle sensor group and contents of the nonvolatile program memory;
Characterized in that the on-vehicle electronic control device further comprises;
a watchdog timer into which a watchdog signal formed of a generated pulse train outputted by the microprocessor is inputted and which, when a pulse width of the watchdog signal is equal to or larger than a predetermined value, generates a reset pulse to reactivate the microprocessor;
a nonvolatile collation information storage means that is connected to the concurrent control circuit via a bus and previously stores predetermined checksum external collation data;
external checksum means for comparing current sum data that concerns data stored in the nonvolatile program memory and is transmitted to the concurrent control circuit from the microprocessor with the checksum external collation data that is previously stored in the collation information storage means, and generating an anomaly detection output when the current sum data does not coincide with the checksum external collation data;
interval monitoring means for generating the anomaly detection output when a time interval for execution by the external checksum means exceeds a predetermined time; and
load group stopping means for stopping a partial drive of the on-vehicle electric load group in response to the anomaly detection output from at least one of the external checksum means and the interval monitoring means.
1 Assignment
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Accused Products
Abstract
An on-vehicle electronic control device is provided, which includes an auxiliary microprocessor and subjects a microprocessor allocated to a main part of control to an external diagnosis, thereby improving reliability of performance. A microprocessor (110a) including a nonvolatile program memory (115a) into which a control program is written is serially connected to an auxiliary microprocessor (120a) including an auxiliary nonvolatile program memory (125). The microprocessor (110a) and the auxiliary microprocessor (120a) functions in cooperation to control on-vehicle electric load groups (104a and 104b) in response to input signals from on-vehicle sensor groups (102a and 102b) and an on-vehicle analog sensor group 103a. The nonvolatile program memory (115a) and the microprocessor (110a) are subjected to runaway monitoring performed by a watchdog timer (130) and to an external checksum diagnosis performed periodically by the auxiliary microprocessor (120a). If an anomaly occurs in the run away monitoring, the external checksum diagnosis, and a checksum interval, parts of electric loads are cut off of power supply by load power relay (107a).
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Citations
17 Claims
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1. An on-vehicle electronic control device, comprising:
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a nonvolatile program memory for storing a control program and a control constant;
a microprocessor which is connected to a first serial-parallel converter via a bus and which executes the control program;
a concurrent control circuit which is serially connected to the microprocessor via a second serial-parallel converter, wherein the microprocessor and the concurrent control circuit function in cooperation to control an on-vehicle electric load group based on input signals from an on-vehicle sensor group and contents of the nonvolatile program memory;
Characterized in that the on-vehicle electronic control device further comprises;
a watchdog timer into which a watchdog signal formed of a generated pulse train outputted by the microprocessor is inputted and which, when a pulse width of the watchdog signal is equal to or larger than a predetermined value, generates a reset pulse to reactivate the microprocessor;
a nonvolatile collation information storage means that is connected to the concurrent control circuit via a bus and previously stores predetermined checksum external collation data;
external checksum means for comparing current sum data that concerns data stored in the nonvolatile program memory and is transmitted to the concurrent control circuit from the microprocessor with the checksum external collation data that is previously stored in the collation information storage means, and generating an anomaly detection output when the current sum data does not coincide with the checksum external collation data;
interval monitoring means for generating the anomaly detection output when a time interval for execution by the external checksum means exceeds a predetermined time; and
load group stopping means for stopping a partial drive of the on-vehicle electric load group in response to the anomaly detection output from at least one of the external checksum means and the interval monitoring means. - View Dependent Claims (2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17)
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Specification