A technique is desired that can output a warning to a user before a buffer of a controller runs out of a free space. A control apparatus includes a buffer for buffering log data sequentially generated, an interface unit connectable with an external storage device, a writing unit for sequentially reading the log data buffered to the buffer and sequentially writing the log data to the external storage device while the external storage device is connected to the interface unit, a monitoring unit for monitoring a free space of the buffer, and a warning unit for outputting a warning upon the free space falling below a prescribed value.

A method is provided that provides data analysis for sequence of events reporting in the operation of an industrial process. A digital filter and edge detector are provided that combines a method for excluding known invalid samples and a method for excluding samples taken while the input in the traveling range. The filtering method reduces the overhead on the CPU from managing the sequence of events machine and allows it to focus on performing safety functions.

A method is provided that provides data analysis for sequence of events reporting in the operation of an industrial process. A digital filter and edge detector are provided that combines a method for excluding known invalid samples and a method for excluding samples taken while the input in the traveling range. The filtering method reduces the overhead on the CPU from managing the sequence of events machine and allows it to focus on performing safety functions.

A technique is desired that can output a warning to a user before a buffer of a controller runs out of a free space. A control apparatus includes a buffer for buffering log data sequentially generated, an interface unit connectable with an external storage device, a writing unit for sequentially reading the log data buffered to the buffer and sequentially writing the log data to the external storage device while the external storage device is connected to the interface unit, a monitoring unit for monitoring a free space of the buffer, and a warning unit for outputting a warning upon the free space falling below a prescribed value.

The invention provides a control device capable of preventing unnecessary stop in the control device including a programmable circuit unit and an arithmetic processing unit, and a method of controlling the control device. In the invention, an abnormality determination unit determines a correspondence between a position of a soft error detected by an error detection unit and a functional unit based on map information including position information (position number) in the FPGA unit corresponding to a functional unit in an FPGA unit. Further, a processor unit continues operating the control device when the abnormality determination unit determines the position of the soft error corresponds to an unused portion of the functional unit, and executes a predetermined process when the abnormality determination unit determines the position of the soft error corresponds to a used portion (e.g. a majority circuit unit or a used circuit unit) of the functional unit.