Patent ID: 6263487
Filing Date: 2001-07-17
Classification: G05B,Y02P

Abstract:
A programmable controller, comprising:an Internet communication interface receiving software function blocks of a control program, the software function blocks being loadable by the programmable controller and capable of being tied to the control program while the control program is being executed by the programmable controller, the control program having a control operation and being processed by the programmable controller at least one of cyclically and via interrupt control; anda software function block execution system including an exe engine object, a watchdog object, a bootstrap object, and an input/output module object, the software function block execution system storing process image inputs and process image outputs, receiving signal states from process inputs, and sending the signal states to process outputs, the bootstrap object generating software function block objects and the input/output module object before a start of the control operation, wherein if the control program is processed cyclically, the bootstrap object sends to the exe engine object a list of the software function block objects to be processed, and wherein if the control program is processed via interrupt control, the bootstrap object sends to the exe engine object a list of the software function block objects to be processed for each of the process inputs, and wherein at the start of the control operation, the bootstrap object starts the exe engine object, the exe engine starting the watchdog object, the watchdog object resetting the exe engine object when a cycle time is exceeded, the exe engine object cyclically i) updates the process image inputs, ii) if the control program is processed cyclically, processes one processing step of the software function block objects, iii) if the control program is processed via interrupt control, determines changes in the signal states at the process inputs and processes the software function block objects assigned to the process inputs, and iv) updates the process image outputs.