Cardi asConfiguration screenManufacturers adhering to the "professional quality, honesty and trustworthiness, the pursuit of excellence" business philosophy, the following sharesSerial screenCommunication protocol and serial interface basic concepts, as we all know: Modbus protocol is applied to electronic controllers on a common language. With this protocol, controllers can communicate with each other, controllers over the network (such as Ethernet) and other devices. It has become a common industrial standard. With it, control equipment produced by different manufacturers can be connected to an industrial network for centralized monitoring. (Generally for industrial use, such as industrial serial screens);

The so-called protocol, can also be understood as the above said "language" bar, simply said software.

This protocol defines a message structure that a controller can recognize the use, regardless of the network through which they are communicated. It describes the process by which a controller requests access to other devices, if requests from other devices are responded to, and how errors are detected and logged. It develops a common format for message domain patterns and content.

When communicating on a Modbus network, this protocol determines that each controller needs to know their device address, identify messages sent by address, and decide what action to do. If a response is required, the controller generates feedback and sends it out with the Modbus protocol. On other networks, messages that contain the Modbus protocol are converted to frames or package structures used on this network.

This conversion also extends the root RS485 as a physical interface (RS485 communication serial screen), simply said to be hardware.

In general, two devices transmit data through the MODBUS protocol:

The earliest is to use RS232C as a hardware interface( that is, the serial communication port (serial port) on ordinary computers);

Also with RS422,

There are also commonly used RS485, this interface transmission distance is far, in the general industrial site used more.

MODBUS PROTOCOL IS DIVIDED INTO MODBUSRTU, MODBUSASCII AND LATER DEVELOPED MODBUS

TCP three modes:

The first two of them (MODBUSRTU, MODBUS)

AsCII) uses the physical hardware interfaces of the Serial (Serial) communication port (RS232, RS422, RS485).

AND MODBUS

TCP is in line with the current trend of today, everything can be connected to the Ethernet network or the Internet, data transmission. So again, MODBUS.

TCP mode, the hardware interface of this mode is the Ethernet port, that is, the network port commonly used on our computers.