Control method for control software execution system
AssigneeMitsubishi Denki Kabushiki Kaisha
InventorShigeki Nankaku
Life of this patent
Estimating the term…
Abstract
To insure that a task is started once and runs for a prespecified time previously allocated for the task, the real time operating system according to the present invention computes lapse of time from a current point of time, writes the computed lapse of time in a counter, and makes the task run after the period of time written in the counter has passed.
Claims11
A control method for a control software execution system in which a scheduler for switching between different tasks is provided in a real time operating system in a memory and a plurality of tasks each for executing control software is executed according to task switch control by said scheduler, the method comprising the steps of:
- changing a value stored in a counter with each cycle of a real time clock;
- reading and recording a first value stored in said counter immediately before a task is started;
- reading and recording a second value stored in said counter immediately after said task is finished;
- computing a last running time for said task from said first and second values;
- computing a total running time for said task from a previous total running time and said last running time;
- and
- recording said computed total running time.
A control method for a control software execution system in which a scheduler for switching between different tasks is provided in a real time operating system in a memory and a plurality of tasks each for executing control software is executed according to task switch control by said scheduler, the method comprising the steps of:
- synchronizing operations of the control software execution system using a system clock having a system clock cycle not less than a time required to execute a task requiring a longest processing time;
- computing a lapse of time from a current point of time to a point of time after which a task is to be run so that the task runs at a prespecified rate, said lapse of time being an integer multiple of a real time clock cycle that is a fraction of the system clock cycle;
- writing said computed lapse of time in a counter;
- making said task run after the lapse of time written in said counter has passed;
- changing a value stored in a second counter with each cycle of the real time clock;
- reading and recording a first value stored in said second counter immediately before a task is started;
- reading and recording a second value stored in said second counter immediately after said task is finished
- computing a last running time for said task from said first and second values;
- computing a total running time for said task from a previous total running time and said last running time;
- recording said computed total running time;
- executing interrupt processing when interrupt is generated with a task having higher dispatching priority order;
- specifying an expected total running rate for each task;
- specifying allowance for a difference between said specified expected total running rate and the actual running time;
- computing an expected total running time from the expected running rate including the specified allowance;
- and
- determining an abnormal state of a task by comparing said expected total running time to the actual running time.
A control method for a control software execution system in which a scheduler for switching between different tasks is provided in a real time operating system in a memory and a plurality of tasks each for executing control software is executed according to task switch control by said scheduler, the method comprising the steps of:
- synchronizing operations of the control software execution system using a system clock having a system clock cycle not less than a time required to execute a task requiring a longest processing time;
- computing a lapse of time from a current point of time to a point of time after which a task is to be run so that the task runs at a prespecified rate, said lapse of time being an integer multiple of a real time clock cycle that is a fraction of the system clock cycle;
- writing said computed lapse of time in a counter;
- making said task run after the lapse of time written in said counter has passed;
- changing a value stored in a second counter with each cycle of the real time clock;
- reading and recording a first value stored in said second counter immediately before a task is started;
- reading and recording a second value stored in said second counter immediately after said task is finished;
- computing a last running time for said task from said first and second values;
- computing a total running time for said task from a previous total running time and said last running time;
- recording said computed total running time;
- executing interrupt processing when interrupt is generated, with a task having higher dispatching order;
- specifying an expected total running rate for each task;
- specifying an allowance for a difference between said expected total running rate and the actual running time;
- computing an expected total running time from the expected running rate including said specified allowance;
- determining an abnormal state of a task by comparing said computed expected total running time to the actual running time;
- determining whether or not said task is one affected by a tool;
- selecting another tool if it has been determined that the task will be affected by the tool;
- and
- restarting execution of a machining program specified by said selected tool.
A control method for a control software execution system in which a scheduler for switching between different tasks is provided in a real time operating system in a memory and a plurality of tasks each for executing control software is executed according to task switch control by said scheduler, the method comprising the steps of:
- synchronizing operations of the control software execution system using a system clock having a system clock cycle not less than a time required to execute a task requiring a longest processing time;
- computing a lapse of time from a current point of time to a point of time after which a task is to be run so that the task runs at a prespecified rate, said lapse of time being an integer multiple of a real time clock cycle that is a fraction of the system clock cycle;
- writing said computed lapse of time in a counter;
- making said task run after the lapse of time written in said counter has passed;
- changing a value stored in a second counter with each cycle of the real time
- reading and recording a first value stored in said second counter immediately before a task is started;
- reading and recording a second value stored in said second counter immediately after said task is finished;
- computing a last running time for said task from said first and second values;
- computing a total running time for said task from a previous total running time and said last running time;
- recording said computed total running time;
- executing interrupt processing when interrupt is generated with a task having higher dispatching priority;
- specifying an expected total running rate for each task;
- specifying an allowance for a difference between said specified expected total running time and the actual running time;
- computing an expected total running time from the expected running rate including said specified allowance;
- determining an abnormal state of a task by comparing said computed expected total running time to the actual running time;
- determining whether or not said task is one affected by a tool feed speed;
- selecting another tool feed speed if it is determined that the task is affected by the tool feed speed;
- and
- restarting execution of a machining program specified by said selected tool feed speed.
A control method for executing control software so as to execute switching between different tasks using a scheduler which is independent of a task priority system in a real time operating system having a plurality of tasks in a memory, the method comprising:
- synchronizing operations of the control software execution system using a system clock having a system clock cycle which is at least equal to a time required to execute that task requiring a longest processing time;
- computing a time period from a first time to a second time after which a task is to be run so that a task runs according to a prespecified parameter from the first time, said time period being an integer multiple of a real time clock period which is a fraction of the system clock cycle;
- writing the time period in a counter;
- and
- running a task after the time period written in the counter has passed.
A control method for executing control software so as to execute switching between different tasks using a scheduler which is independent of a task priority system, in a real time operating system having a plurality of tasks in a memory, the method comprising:
- synchronizing operations between an external event and a task of the control software execution system, using a system clock having a system clock cycle which is at least equal to a time required to execute that task requiring a longest processing time;
- computing a time period from a first time to a second time after which a task is to be run so that a task runs according to a prespecified parameter from the current time, said time period being an integer multiple of a real time clock period which is a fraction of the system clock cycle;
- writing the time period in a counter;
- and
- running a task after the time period written in the counter has passed.
Dependencies are inferred from the claim text.