CPU configuration

CPU is the core of the PLC, acts as the nerve center of each PLC have at least one CPU, which functions according to the program given to the PLC system to receive and store user programmable logic controller programs and data collected by way of scanning the input device sent by the field state or data, and stored in the specified register, while the diagnostic power and the PLC internal circuit operating status and programming syntax errors. After entering the run, one by one to read the instructions from the user program memory, then the task was analyzed by Directive generate corresponding control signals to command associated control circuitry. CPU mainly by the operator, controller, register and data connections between them, control and status bus constituted, CPU unit also includes a peripheral chip bus interface and related circuitry. The main memory used to store programs and data, is an indispensable component PLC unit. In the user view, unnecessarily detailed analysis of the internal circuitry of the CPU, but each plc digital input output io module part is working mechanism should be enough to understand.CPU controller controls the work, which it reads the instruction, the instruction interpretation and execution of instructions. However, the pace of work is controlled by the oscillation signal. Operator used for digital or logic operations, working under the command of the controller. Register to participate in operations, and store intermediate result of the operation, it is also working under the command of the controller. CPU speed and memory capacity are important parameters for the PLC, which determines the operating speed of the PLC, IO, and the number of software capacity, etc., thus limiting the size of the control.