Method for consistent storage of data in an industrial controller

#The present invention generally relates to industrial control systems and in particular to providing a file system on an industrial controller and a system and methods for employing the file system.

#Industrial controllers are special purpose computers used for controlling factory automation devices. Under the direction of a stored program, a processor of the industrial controller examines a series of inputs reflecting the status of a controlled process or device and changes outputs affecting control of the controlled process or device. Generally industrial controllers are constructed in modular fashion to accommodate different applications requiring different numbers and types of input/output (I/O) circuits as is determined by the particular device or process being controlled. The stored control program runs in real-time to provide outputs to the controlled process as electrical signals to outputs such as actuators and the like. The outputs are based on the logic of the control program and inputs received from sensors of the controlled process.

#The industrial controller or programmed logic controller (PLC) executes a series of operations that are performed sequentially and repeatedly. In general, the series of operations includes an input scan, a program scan and an output scan. During the input scan the PLC examines the on or off state of the external inputs and saves these states temporarily in memory (e.g., a file). During the program scan the PLC scans the instruction of the program and uses the input status to determine if an output will be energized. The output results are then saved to memory (e.g., a file). During the output scan the controller will energize or de-energize the outputs based on the output results stored in memory to control the external devices.

#FIG. 1 illustrates a block schematic diagram of an industrial controller employing a file system in accordance with one aspect of the present invention.

#FIG. 2 illustrates a block diagram of an industrial controller employing a file system to access files remote from the industrial controller in accordance with one aspect of the present invention.

#FIG. 3 illustrates an example of a record instruction for implementing into a ladder logic program in accordance with one aspect of the present invention.

#The present invention will now be described with reference to the drawings. The present invention will be described with reference to a system and method for employing a file system and file system services on an industrial controller. An execution engine is provided that interprets instructions included in an industrial control program. The instructions utilize services in the file system for including user defined routine files loaded from local or remote locations, to load and unload recipe files from local and remote locations, to log and retrieve measured data and trend data to files at local or remote locations, to select different operating systems and to select a running program from a plurality of running programs utilizing the file system. It is to be appreciated that a number of other functions and services can be employed utilizing the services of the file system in accordance with the present invention. Although the present examples will be illustrated with respect to an implementation using ladder logic programs, other industrial control programming languages can be employed and still fall within the scope of the present invention and appended claims.

#The present invention provides a system for multiple files on a single device. The file system provides a common interface for all non-volatile storage devices, such as CompactFlash cards, Windows CE platforms and hard drives that access the file system through a set of common services, such as Get File Information, Read File, Write File, Create File, Delete File, Open File, Close File, etc. The present invention provides for multiple types of data to be stored such as user programs, data logging, recipe storage, operating system updates and program transfers. The present invention supports lean manufacturing by allowing quick reconfiguring of manufacturing environments, allowing user's to load a specific application into the controller “on demand” without downloading from programming software and allows user's to purchase smaller memory processors.

#FIG. 1 illustrates an industrial controller 10 having a file system 24 stored in a program memory 20. The file system 24 can be accessed through a set of common file services. For example, the set of common file services can include services such as Get File Information, Read File, Write File, Create File, Delete File, Open File, Close File, etc. The file system 24 can include a file manager that includes functions for managing the files, such as moving, deleting and copying files. An application program residing on the industrial controller can utilize the file system to perform a variety of functions previously performed within the application program or through an editor. The industrial controller 10 includes a serial port 14 and a network port 16 both coupled to a microcontroller 12. The serial port 14 and network port 16 provides a communication link to remote devices. The microcontroller 12 is also coupled to a backplane bus 18 for providing instructions and receiving inputs from I/O modules. The program memory 20 provides the microcontroller 12 with the execution code necessary to communicate to other devices through the serial port 14, the network port 16 and the backplane bus 18. The program memory also includes the algorithms and calculations necessary for the particular process that the industrial controller is controlling.