rs485 pinout

I wrote a very early serial communication code. However, today is also used to do a simple class encapsulation.Code, such as the following:Rs485Test.h#include Rs485Test.cpp#include "rs485Test.h" int speed_arr[] ={B115200, B38400, B19200, B9600, B4800, B2400, B1200, B300};int name_arr[] ={115 200, 38400, 19200, 9600, 4800, 2400, 1200, 300}; rs485::rs485 (char *name,int speed,int parity,int databits,int st

Win32 serial Programming Author: Han yaoxu In industrial control, Industrial Computer (generally based on Windows) often needs to communicate with smart meters through serial ports. Serial Communication is convenient and widely used.Generally, the Industrial Computer communicates with each smart meter through RS485 bus. The RS485 communication mode is half-duplex and can only be round-robin by the indus

terminal and No 9-pin D-type socket, you need to use the active Terminal module as a Profibus bus terminal (6ES7 972-0da00-0aa0).Figure 6 Profibus active Terminal moduleIf the Profibus cable is not long enough, you need to connect the two cables, you can not simply twist the two copper cores, because this will damage the characteristic impedance of the cable, may lead to communication problems. It is best to use the connector in Figure 7 to connect two cables that need to be connected.Figure 7

program to the. NET Micro framework system, let. NET Micro The Framework Development Board directly accesses the PLC. The difference is that the Red Bull development of COM3 directly support RS485 communication, so we and the PLC directly connected with two lines can be communicated, in addition to the RS485 is Half-duplex communication, so you need to manually send and receive a switch, in addition to th

networked to form distributed systems that allow up to 32 drives and 32 receivers. In the past, the communication between PC and intelligent device relies on RS232, RS485, Ethernet, etc., mainly depends on the interface specification of the equipment. However, RS232, RS485 can only represent the physical media layer and link layer of communication, if you want to achieve two-way access to data, you must w

Abstract: This paper discusses how to use the serial port with FIFO to reduce the number of received interrupts, and gives the frame packing method through a custom communication protocol format, and then introduces a special serial port data sending method, which can improve the response speed of the system in case of avoiding the use of serial port sending interrupt. 1. Introduction The serial port is widely used because of its simple use and low price, and with

-232, RS-422 and RS-485 standards only to interface electrical characteristics to make provisions, and does not involve connectors, cables or protocols, on this basis, users can establish their own high-level communication protocols. The most frequently used plug-ins we encounter in our actual work have three DB9 DB25 RJ45 plug-ins. The above three plug-ins can be used as serial port plug-ins, you can also switch between sockets through cables. Next we will describe the pin definitions of the th

1. What is a stored procedureMysql> delimiter;mysql> CREATE PROCEDURE Proc1 (out s int)-select COUNT (*) into-s from MySQL.User -End---//mysql> delimiter;mysql> call Proc1 (@s);mysql> select @s;2. Create a stored procedureCREATE PROCEDURE ([[in] |out |inout])2.1. In valuesmysql> delimiter;mysql> CREATE PROCEDURE pin (in p_in int), begin, select p_in;Set p_in=2;Select P_in; -End--//mysql> delimiter;mysql> set @p_in =1;mysql> call Pin (@p_in);mysql> select @p_in;2.2. Out valuesExample 1:mysql> del

protocol, as long as the single-chip microcomputer in accordance with the Modbus protocol to send and receive data, you can communicate. The touch screen and MCU are connected directly with RS-232 or RS-485 standard interface, and the transfer rate is set to 9600bps. Figure 1 is the circuit diagram of the system. Figure 1 System circuit diagram Set AT89S51 microcontroller Txd, rxd port to asynchronous serial communication mode, after the MAX485 chip to convert TTL level to

selection of standard power cords.Controller signal line The Controller has three signal lines connected to the card reader 4 ~ 9-core), lock status sensor 2-core in the electric lock) and 2-core push button ). These three signal lines can be replaced by twisted pair wires in integrated cabling. To avoid electromagnetic interference in space, the signal line of the card reader should be shielded. The other two signal lines can be shielded or non-shielded. Remote signal line There is a signal li

, the selection of standard power cords. Controller signal line The Controller has three signal lines connected to the card reader (4 ~ 9-core), lock status sensor (2-core) and push button (2-core) in the electric lock ). These three signal lines can be replaced by twisted pair wires in integrated cabling. To avoid electromagnetic interference in space, the signal line of the card reader should be shielded. The other two signal lines can be shielded or non-shielded. Remote signal line There is a

RS-232, RS-422 and RS-485 standards only to interface electrical characteristics to make provisions, and does not involve connectors, cables or protocols, on this basis, users can establish their own high-level communication protocols. The most frequently used plug-ins we encounter in our actual work have three DB9 DB25 RJ45 plug-ins. The above three plug-ins can be used as serial port plug-ins, you can also switch between sockets through cables. Next we will describe the pin definitions of the

(m_osWrite.hEvent,1000);return dwBytesWritten;}return 0;}return dwBytesWritten; (4) disable the serial port Using the API function to close the serial port is very simple. You only need to use the handle returned by the createfile function as the parameter to call closehandle: BOOL CloseHandle( HANDLE hObject; //handle to object to close ); An example of serial ProgrammingTo help you better understand the serial programming, We will compile two routines (see the source code section ).The seri

/* ------ + ------An example of serial ProgrammingTo help you better understand serial programming, We will compile two routines (see the source code section ),Both routines implement serial communication between the industrial computer and the Baxter display instrument through the RS485 interface. WhereThe first routine uses synchronous serial port operations, and the second routine uses asynchronous serial port operations.We will only introduce the

Arm Embedded systems often encounter multiple serial port application requirements, and arm chip system native UART number is limited, so it is necessary to extend more interfaces through other high-speed bus. In this paper, Toradex based on the NXPI.MX6D/6Q processor Apalis i.mx6d/q arm computer module, the Linux system through the Exar scheme to expand the 8-channel serial port. The Apalis i.mx6d/q module itself can support up to 5 UART serial port outputs. Compatible with high speed tia/eia-2

In Ise, the set pin can be constrained by opening the Assign package pins in user constraints. Xilinx pack-[design Object list-i/o Pin opened] Where the parameters are set as follows I/O name--io pin name, corresponding to the input and output pins in module. I/O Direction--Sets the input or output pin. Loc-Located on the chip. Bank-the bank block where the pin is located, and when LOC is specified, the bank is determined. FROM:SPARTAN-3E FPGA series Data Sheet P19 I/O Std. Leve

original local programming and control. Gradually tending to remotely manage control sessions.Two. The development trend of PLC communication mode changes:The main communication modes of PLC are RS232, RS485, Ppi/mpi, PROFIBUS dp/pa/fms Fieldbus, Ethernet bus, DEVICEnet bus, and wireless network.With the limitations of local communication control, remote control of networked communications, wired and wireless access to the mainstream slowly. Ethernet

and distribution, building automation, mechanical processes, locomotives, railway transportation, shipping and shipbuilding, Metro, food and beverage industry, nuclear industry, chemical industry, aviation and aerospace, automotive manufacturing and other automation control areas.3. PROFIBUSProfibus is the Fieldbus standard for German national standards DIN19245 and European standard EN50170. The PROFIBUS series is made up of PROFIBUS-DP,PROFIBUS-FMS,PROFIBUS-PA. The technology was launched by

levels up to ip30Wide Power Supply settings, input range reaches 5 ~ 35 VThe RS232/RS485/rs422 interface adopts built-in 15 kV ESD protection to prevent static damage.RS485/rs422 interface with built-in 4kv Lightning ProtectionThe power interface adopts built-in reverse protection and overvoltage protection.Gpio, A/D ports, built-in short-circuit and overvoltage protectionLightning Protection for antenna interfaces (optional)4kv lightning protection

Now let's talk about the port remapping of the STM32 microcontroller, as it is an example of itself. Here is an example of the remapping of the USART1:Because I want a TFT_LCD screen of the main control board, taking into account the FSMC I chose the STM32F103VCT6 model of the CPU, accidentally connected to the serial port USART1. Because in the tuning process only found wrong, there is no way, can only be resolved by port remapping. But it didn't work. Port remapping , only the name, not the bo