Method and device for monitoring a process execution

• US 7,895,478 B2
• Filed: 12/30/2005
• Issued: 02/22/2011
• Est. Priority Date: 02/28/2005
• Status: Active Grant

• Current Assignee: Robert Bosch GmbH
• Original Assignee: Robert Bosch GmbH
• Inventors: Jansen, Alexander, Karner, Ruediger
• Primary Examiner(s): Wilson; Yolanda L
• Application Number:
  US11/885,294
• Publication Number:
  US 20090300435A1
• Time in Patent Office: 1,880 Days
• Field of Search: 714/55, 714/15, 714 10- 13, 702/125, 700/1, 701/29, 701/45
• US Class Current: 714/55
• CPC Class Codes: G05B 19/0428 Safety, monitoring G05B19/0423 takes precedence
• CPC Class Codes: G05B 2219/24125 Watchdog, check at timed intervals
• CPC Class Codes: G06F 11/0757 by exceeding a time limit, i.e. time-out, e.g. watchdogs

Abstract

A method for monitoring a process execution of a plurality of sequentially executed processes starts one of a plurality of timers in cyclic permutation when one of the processes is started, and outputs a first error signal when a period of time recorded by one of the timers exceeds a predefined maximum period of time.

Claims

1. A method for monitoring a processor system, the method comprising:

executing a plurality of processes, one of the processes being started after a preceding one of the processes is ended, wherein one of at least two timers is restarted in cyclic permutation when one of the processes is started; and

outputting a first error signal when a period of time recorded by one of the at least two timers exceeds a predefined maximum period of time;

wherein, in response to an ending of a process, a recorded period of time of a corresponding timer, which is restarted by a next process to be executed, is read out, and wherein a second error signal is output when a recorded period of time falls below a predefined minimal period of time.

2. The method of claim 1, wherein one of the processes is started, at the earliest, following a predefined time interval that has elapsed since the start of another of the processes that was started immediately prior to the one of the processes.

3. The method of claim 2, wherein:

a length of the maximum period of time is defined by N dT<

T_Max<

(N+1) dT;

T_Max is the maximum period of time;

dT is the predefined time interval;

N is a number of the timers;

N dT is a first product of the predefined time interval and of the number of timers; and

(N+1) dT is a sum of the first product and of the predefined time interval.

4. A method for monitoring a processor system, the method comprising:

executing a plurality of processes, one of the processes being started after a preceding one of the processes is ended, wherein one of at least two timers is restarted in cyclic permutation when one of the processes is started; and

outputting a first error signal when a period of time recorded by one of the at least two timers exceeds a predefined maximum period of time;

wherein a test datum is transmitted for processing to a started process, and wherein upon termination of the process, a second error signal is output in response to a deviation of the processed test datum from a setpoint value.

5. The method of claim 4, wherein a process includes subprocesses, and at least one of the subprocesses executes an operation on the test datum which confirms an execution of the at least one of the subprocesses reproducibly by the processed test datum.

6. The method of claim 5, wherein at least two subprocesses execute mutually non-commutative operations on the test datum, so that the execution of the at least two subprocesses in a correct sequence is able to be confirmed by the processed test datum.

7. The method of claim 4, wherein one of the processes is started, at the earliest, following a predefined time interval that has elapsed since the start of another of the processes that was started immediately prior to the one of the processes.

8. The method of claim 7, wherein:

a length of the maximum period of time is defined by N dT<

T_Max<

(N+1) dT;

T_Max is the maximum period of time;

dT is the predefined time interval;

N is a number of the timers;

N dT is a first product of the predefined time interval and of the number of timers; and

(N+1) dT is a sum of the first product and of the predefined time interval.

9. A method for monitoring a processor system, the method comprising:

executing a plurality of processes, one of the processes being started after a preceding one of the processes is ended, wherein one of at least two timers is restarted in cyclic permutation when one of the processes is started; and

outputting a first error signal when a period of time recorded by one of the at least two timers exceeds a predefined maximum period of time;

wherein;

one of the processes is started, at the earliest, following a predefined time interval that has elapsed since the start of another of the processes that was started immediately prior to the one of the processes;

a second error signal is output when a recorded period of time falls below a predefined minimal period of time;

the minimal period of time is greater than or equal to (N−

1) dT;

dT is the predefined time interval; and

N is a of the number of the timers.

10. The method of claim 9, wherein:

a length of the maximum period of time is defined by N dT<

T_Max<

(N+1) dT;

T_Max is the maximum period of time;

N dT is a first product of the predefined time interval and of the number of timers; and

(N+1) dT is a sum of the first product and of the predefined time interval.

11. A device for monitoring a processor system, comprising:

a monitoring device, which is linked to the processor system to receive a start signal from the processor system when a process is started;

at least two timers connected to a multiplexer of the monitoring device to cyclically restart the timers using a reset signal, and which are connected to an input of the monitoring device to transmit a recorded period of time to the monitoring device;

wherein;

a plurality of the processes are executed, one of the processes being started after a preceding one of the processes is ended;

one of at least two timers is restarted in cyclic permutation when one of the processes is started;

a first error signal is outputted when a period of time recorded by one of the at least two timers exceeds a predefined maximum period of time; and

the monitoring device has a comparator to compare a setpoint value to a test datum processed by the process, and to output a second error signal for a deviation.

12. The device of claim 11, wherein the timers are regressively operated counters which, in a restart, are set to a value that corresponds to the predefined maximal period of time.

13. The device of claim 12, wherein the input is configured to trigger an output of the first error message when a zero of one of the counters is present at the input.

14. The device of claim 11, wherein the count of the counters is able to be read out by the monitoring device, and the timer is configured to be stoppable by a control signal.

15. The device of claim 11, wherein a process includes subprocesses, and at least one of the subprocesses executes an operation on the test datum which confirms an execution of the at least one of the subprocesses reproducibly by the processed test datum.

16. The device of claim 15, wherein at least two subprocesses execute mutually non-commutative operations on the test datum, so that the execution of the at least two subprocesses in a correct sequence is able to be confirmed by the processed test datum.

17. The device of claim 11, wherein:

one of the processes is started, at the earliest, following a predefined time interval that has elapsed since the start of another of the processes that was started immediately prior to the one of the processes;

a length of the maximum period of time is defined by N dT<

T_Max<

(N+1) dT;

T_Max is the maximum period of time;

dT is the predefined time interval;

N is a number of the timers;

N dT is a first product of the predefined time interval and of the number of timers; and

(N+1) dT is a sum of the first product and of the predefined time interval.

18. A device for monitoring a processor system, comprising:

a monitoring device, which is linked to the processor system to receive a start signal from the processor system when a process is started;

at least two timers connected to a multiplexer of the monitoring device to cyclically restart the timers using a reset signal, and which are connected to an input of the monitoring device to transmit a recorded period of time to the monitoring device;

wherein;

a plurality of the processes are executed, one of the processes being started after a preceding one of the processes is ended;

one of at least two timers is restarted in cyclic permutation when one of the processes is started;

a first error signal is outputted when a period of time recorded by one of the at least two timers exceeds a predefined maximum period of time;

in response to an ending of a process, a recorded period of time of a corresponding timer, which is restarted by a next process to be executed, is read out; and

a second error signal is output when a recorded period of time falls below a predefined minimal period of time.

19. A device for monitoring a processor system, comprising:

a monitoring device, which is linked to the processor system to receive a start signal from the processor system when a process is started;

at least two timers connected to a multiplexer of the monitoring device to cyclically restart the timers using a reset signal, and which are connected to an input of the monitoring device to transmit a recorded period of time to the monitoring device;

wherein;

a plurality of the processes are executed, one of the processes being started after a preceding one of the processes is ended;

one of at least two timers is restarted in cyclic permutation when one of the processes is started;

a first error signal is outputted when a period of time recorded by one of the at least two timers exceeds a predefined maximum period of time;

one of the processes is started, at the earliest, following a predefined time interval that has elapsed since the start of another of the processes that was started immediately prior to the one of the processes;

a second error signal is output when a recorded period of time falls below a predefined minimal period of time;

the minimal period of time is greater than or equal to (N−

1) dT;

dT is the predefined time interval; and

N is a of the number of the timers.

20. A method for monitoring a processor system, the method comprising:

sequentially executing a plurality of processes, a predefined time interval dT being assigned to each of the plurality of processes such that, for each respective one of the processes, a process to be executed following the respective process is not started at least until lapse of the predefined time interval measured from a start of execution of the respective process;

restarting a first of a plurality of timers upon a respective start of each of a first subset of the sequentially executed plurality of processes and not upon a respective start of any of a second subset of the sequentially executed plurality of processes;

restarting a second of the plurality of timers upon the respective start of each of the second subset of the sequentially executed processes and not upon the respective start of any of the first of the sequentially executed plurality of processes; and

outputting an error signal when a period of time recorded by one of the first and second timers exceeds a predefined maximum period of time;

wherein;

for each of the plurality of timers, after the respective timer is restarted upon the respective start of one of the respective subset of the sequentially executed plurality of processes upon start of which the respective timer is configured to be restarted, where an error does not occur, the respective timer is restarted only after successive execution of a number of the sequentially executed plurality of processes at least equal to a number N of the plurality of timers configured to be restarted upon each respective start of a respective subset of the plurality of processes; and

a length of the maximum period of time T_Max is defined by (N*dT)<

T_Max<

((N+1)*dT).

21. A method for monitoring a processor system, the method comprising:

sequentially executing a plurality of processes, a predefined time interval dT being assigned to each of the plurality of processes such that, for each respective one of the processes, a process to be executed following the respective process is not started at least until lapse of the predefined time interval measured from a start of execution of the respective process;

restarting a first of a plurality of timers upon a respective start of each of a first subset of the sequentially executed plurality of processes and not upon a respective start of any of a second subset of the sequentially executed plurality of processes;

restarting a second of the plurality of timers upon the respective start of each of the second subset of the sequentially executed processes and not upon the respective start of any of the first of the sequentially executed plurality of processes; and

outputting an error signal when a period of time recorded by one of the first and second timers is less than a predefined minimal period of time;

wherein;

for each of the plurality of timers, after the respective timer is restarted upon the respective start of one of the respective subset of the sequentially executed plurality of processes upon start of which the respective timer is configured to be restarted, where an error does not occur, the respective timer is resstarted only after successive execution of a number of the sequentially executed plurality of processes at least equal to a number N of the plurality of timers configured to be restarted upon each respective start of a respective subset of the plurality of processes; and

a length of the minimal period of time T_Min is defined by ((N−

1)*dT)≧

T_Min .