摘要:
A redundant controller employs two controller chassis having replaceable functional modules interconnected electrically within the chassis. System back up modules in the chassis coordinate the switching of control from a primary to a secondary chassis according to chassis redundancy state information of the chassis stored in the backup modules and module redundancy state information stored in the modules unique to the modules.
摘要:
The present invention constitutes a data crossloading system for use with a programmable controller system having primary and secondary (or "back-up") systems each of which have redundant hardware components and have data structures associated with these components. The present invention further relates to the interconnection of the hardware components and to the processes for providing redundant data structures which enable a secondary or back-up system to rapidly and effectively assume control when a malfunction occurs in a primary control system. Both systems are connected via the same remote data links to common I/O racks which interface to sensing and output devices on the equipment being controlled. Data structure information in the primary system is specially crossloaded to the secondary system so that when a malfunction occurs that shuts down the primary system, the secondary system can begin execution of the same control programs and input and output the same data to the same I/O racks based on up to date data from the primary system. The crossloading of the data is accomplished through the use of special backup modules in both the primary and secondary (backup) control systems connected by a high speed communications link. Communications take place through the use of program utilities which establish a tightly coupled communications network between the primary and secondary systems. Additionally, on-line editing is enabled in stages so that when either control system can not properly execute the edit it is rejected. This system insures that edits can not take place in the primary system without being concurrently implemented in the secondary system.
摘要:
A programmable controller for operating a machine to perform programmed functions allows the user to allocate the amount of processing time to be devoted to a machine control program and to user defined background tasks. The allocation is defined by an entry stored in one of several locations in a data table. Each occurrence of a timed interrupt steps the operating system through the data table. When the operating system accesses the location at which the entry is stored, the machine control program is assigned as lower execution priority than any background tasks to be executed. When the last storage location of the data table is accessed, the user control program is restored to a higher execution priority than the background tasks before initiating another stepping sequence through the data table.
摘要:
An industrial control system employs a primary and secondary controller each having a processor and at least one I/O data table. Updating of the secondary processor's I/O data table is performed prior to the same data being transmitted to the controlled process. This eliminates possible retrogressive control at the time of switch-over of control from the primary industrial controller to the secondary industrial controller. Additional I/O data tables may be provided in each of the primary and secondary industrial controllers. In the case of the secondary industrial controller, this duplicate I/O data table temporarily holds data until the transmission is complete preventing the partial update of the working I/O data table of the secondary industrial controller. The duplicate I/O data table in the primary industrial controller allows simultaneous outputting of the I/O data transmitted to the controlled process without corruption while the user program of the primary industrial controller resumes execution.
摘要:
On-line upgrading of a primary industrial controller is provided through the use of a secondary industrial controller that may assume control of the process controlled by the primary industrial controller. A switch-over of control is orchestrated by a system back-up module that may detect removal of the functional components of the primary industrial controller to initiate the switch-over. Determination of removal of functional modules may be provided by a periodic polling of the functional components on the interconnecting communication link. The system back-up module designates one of the functional modules to poll the system back-up module so that complete coverage of removable components may be had.
摘要:
A programmable controller suitable for operating a machine to carry out a plurality of programmed functions includes a plurality of program processors each being operable to execute simultaneously a different control program that directs the programmable controller to operate the machine to perform specific functions. Each of the processors includes a memory having areas for receiving different priority level messages. Each area has an addressable location corresponding to each module in the controller that can send messages. A message may be an executable command or a pointer to an address block containing the message or message access parameters.
摘要:
An industrial controller provides a primary controller and a redundant secondary controller and allows switchover between the controllers in the event of a failure in the primary controller. The process of qualification of the secondary controller in which its programming is made to match the primary controller may be inhibited to permit the secondary controller to maintain a clean version of an upgraded program executing on the primary controller. The clean program may be reverted to in the event an upgrading of the program in the primary controller is unsuccessful. Switchover is permitted even though the qualification of the secondary controller is not enabled.
摘要:
An industrial control system employs a primary and secondary controller each having a processor and at least one I/O data table. Updating of the secondary processor's I/O data table is performed prior to the same data being transmitted to the controlled process. This eliminates possible retrogressive control at the time of switch-over of control from the primary industrial controller to the secondary industrial controller. Additional I/O data tables may be provided in each of the primary and secondary industrial controllers. In the case of the secondary industrial controller, this duplicate I/O data table temporarily holds data until the transmission is complete preventing the partial update of the working I/O data table of the secondary industrial controller. The duplicate I/O data table in the primary industrial controller allows simultaneous outputting of the I/O data transmitted to the controlled process without corruption while the user program of the primary industrial controller resumes execution.
摘要:
A programmable controller for operating a machine to carry out programmed functions includes a plurality of program processors. Each of the program processors is operable to execute simultaneously a different user control program that directs the operation of the machine to perform specific functions. Each of the program processors includes a memory for storing the user control programs and function chart data. The function chart data comprises a series of descriptor files each of which contain an identification of a user control program to execute, a transition condition that indicates when the execution of that user control program is to terminate, and which descriptor file is to be processed next as well as the program processors to process it. A mechanism is also provided to enable the program processors to execute other programs in as background tasks without adversely affecting the execution of the control programs.
摘要:
A redundant controller employs connection-based messaging to ensure reliability and determinacy in communications. The need to close connections and reopen connections with a backup module when control switches from a primary controller to a secondary controller is eliminated by keeping the secondary controller updated as to the connections that have been opened and having the secondary controller assume the connection identification numbers of the primary controller upon switch-over.