The production and application of embedded PLC

Embedded programmable controller, which embeds the ladder diagram language commonly used in PLC into the development of single-chip microcomputer, realizes the single-chip microcomputerization of PLC. There are currently two ways. One is to directly embed the ladder diagram compiler into the single-chip microcomputer. The user can communicate directly with the single-chip microcomputer system through the ladder diagram editor and download the saved PMW file directly to the single-chip microcomputer system; the other is to separate the ladder diagram compiler, convert the PMW file into the target code of the single-chip microcomputer through the conversion software, and then burn it into the single-chip microcomputer. The instructions of the PLC used in these two methods are restricted by the ladder diagram compiler or conversion software. The former is like the conventional way of using PLC, and can be monitored and operated through the ladder diagram editing software, but the pin allocation of the single-chip microcomputer used in the PLC hardware cannot be changed once the hardware system design is finalized. The latter is more flexible, and the pin allocation of the single-chip microcomputer can be changed as needed as long as it is within the range allowed by the conversion software. Different hardware circuits can be customized according to application requirements, and the PMW file can be converted into target code according to the actual system. The development of single-chip microcomputer products has changed from using assembly language or C51 language to using ladder diagram language, so that front-line personnel who have no assembly language or C51 computer language programming foundation and understand the relay-contactor control principle can learn and apply single-chip microcomputer control technology through various powerful application functions provided by the ladder diagram programming platform. This article adopts the latter method and takes a 16-point input and 14-point output switch embedded programmable controller as an example to introduce its hardware composition, software resources, and application cases.