simply modbus

After the completion of the previous work, we can achieve targeted applications, first of all, we implement Modbus TCP server-side application. Of course, we do not do specific applications, but the Modbus TCP server-side applications are encapsulated to be called when necessary.Here we do not involve TCP protocol, this part is not necessarily related to Modbus,

ObjectiveThis article uses a NuGet-exposed component technology to implement a Modbus TCP server-side data engine that facilitates the reception of data from a variety of devices.You can download the installation in the NuGet Manager in Visual Studio, or you can enter the following instructions directly in the NuGet console to install:Install-package hslcommunicationNuGet Installation Tutorial Http://www.cnblogs.com/dathlin/p/7705014.htmlQQ Group of T

 I. Introduction of Modbus protocol Modbus protocol is a common language used in electronic controller. With this protocol, controllers can communicate between each other, the controller through the network (for example, Ethernet) and other devices. It has become a general industry standard. With it, the control equipment produced by different manufacturers can be connected to an industrial network for

; } }Where the Loghelper code is not written here, because it has nothing to do with the topic, if you want to run the above code, comments on the line, I personally recommend that the code is not necessary to run a bit, see to understand the line. To run this thing, something will delay too much time. Here the IP and port numbers are provided by the device side. The real program typically writes these two parameters to the configuration file. After the device is connected, the

. That's the way the lights are connected in the picture.Example use COM7 to communicate, in fact, we will be a USB (through the string) into the RS485 bus to communicate, hang a station address is 01, baud rate 9600, check None (N), data bit 8, stop 1.Ohsce_eng_serial_creat($hscecom,"com7",1,0,9600,‘n‘,8,1); //我们创建了一个串口资源并存入了$hscecom变量中，串口为com7,权限为1（写读）,方式0（默认），波特率9600，无校验，数据位8，停止位1A more detailed description of the function is described in the manual: Ohsce_eng_serial_creat[Here is a little at

In this section we encapsulate the last application (Modbus RTU Master application), and the development of the RTU Master is consistent with the development of the TCP client. The same we do not do specific applications, but to achieve the basic function of the main station RTU. We encapsulate the functionality of the RTU master as a function to invoke when developing a specific application.For the RTU Master station we mainly achieve two functions:

not (N ), data bit 8, stop 1. Ohsce_eng_serial_creat ($ hscecom, "com7", 9600, 'n',); // we created a serial port resource and saved it to the $ hscecom variable. The serial port is com7, the permission is 1 (write and read), the method is 0 (default), the baud rate is 9600, no verification, data bit 8, stop bit 1 For more details about this function, see the manual Ohsce_eng_serial_creat. [Note that some WINDOWS friends must check that the serial port timeout mechanism has been enabled and set

a broadcast manner. The Modbus protocol establishes the format of the main device query: The device (or broadcast) address, the function code, all data to be sent, and an error detection domain.The response message from the device also has the Modbus protocol component, which includes confirming the domain to be acted on, any data to be returned, and an error detection domain. If an error occurs during mes

the next option letter in the argv, This letter corresponds to the letter in the parameter optstring. If the letter in the option string is followed by a colon ":", it indicates that there are also related parameters, The global variable Optarg points to this extra parameter. If getopt () does not find a matching parameter, the error message is printed and the whole domain Variable optopt set to "?" Character, if you do not want getopt () to print error messages,

complete the required functionality. 　　 　　 6. Exception Code 　　 When something goes wrong, a series of defined exception codes are sent back from the station. Note that the main station will "speculate" to send instructions, using the received success or exception code to determine which modbus the device is willing to respond to and from the station different available data area size. 　　 All exceptions are marked by adding 0x80 to the requ