Enhanced programmable logic controller (PLC)

Abstract

The invention discloses an enhanced programmable logic controller (PLC) which is characterized in that: a communication module includes a USB interface module, a CAN communication interface module, and an RS-485 communication interface module; the USB interface module is connected to a processor chip; the CAN communication interface module is connected to the processor chip through a CAN interface isolating circuit; and the RS-485 communication interface module is connected to the processor chip through an RS-485 bus isolating circuit. The advantages are that: the enhanced PLC has strong flexibility; 5V direct current can be provided to the enhanced PLC through the USB interface module, and meanwhile a circuit operation state can be transmitted to an outer part to be analyzed; and signals of the CAN communication interface module and the RS-485 communication interface module are isolated from the processor chip, so that interference on the chip of the enhanced PLC can be reduced.

Description

technical field [0001] The invention relates to a programmable controller, especially an enhanced programmable controller. Background technique [0002] Programmable controller is an electronic system for digital operations. It uses a type of programmable memory for internal storage programs to perform user-oriented instructions such as logic operations, sequential operations, timing, calculations, and arithmetic operations. Or analog signal input and output to control various types of machinery or production processes. At present, the most commonly used small programmable controllers mainly use a single bus communication or their own communication protocols, which have poor adaptability and reliability when they need to communicate with multiple devices with different protocols and different interference levels at the same time; and the commonly used small Programmable controllers generally do not have analog input / output interfaces, and usually need to add additional anal...

AI Technical Summary

Problems solved by technology

However, each module in the communication interface of the above-mentioned enhanced programmable controller is directly connected to the CPU. When there is a strong interference source in the communication target, it may cause problems such as CPU restart, malfunction or crash, thereby causing system failure and insufficient stability. ; When it is necessary to debug or write programs to a large number of this circuit board, it is necessary to connect an external 24V power supply voltage, the work efficiency is not high, and the operating status of the circuit cannot be effectively monitored in real time

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