lora digitales übertragungsterminal

Based on the research on Lora communication, the Lora communication data terminal and its data processing method based on circular queue buffering are designed. The data terminal uses the circular queue to buffer the received data, and checks, judges and optimizes the data frames one by one. Buffer content, and finally send the data to the monitoring host through the W5100 network interface chip. Lora communication data terminal can buffer, check and judge the dense data received from smart iron shoes, and then optimize the buffer content, improving effectively the stability and reliability of data transmission, which has very important theoretical significance and guarantee for safe railway operation. Practical value.

ZHC0561-lora data transmission terminal is developed by Zongheng Intelligent Control. It is a low-frequency half-duplex LoRa data transmission terminal that supports point-to-point communication protocol. It has 2DO, 4DI, local logic settings and inter-device logic settings, and supports AES communication encryption. Using the serial port for sending and receiving lowers the threshold for wireless applications and enables data transmission from the serial port to LoRa. LoRa has the advantages of concentrated power density and strong anti-interference ability. The communication distance of this product can reach 8000m (open line of sight, antenna gain 3dBi, height greater than 2m, 0.268K air rate, default channel).

lora digital transmission terminal function

***Tips: The following is just a text introduction. If you need to know more about the functions of this product, you can check it out on the “Product Display” page of this site! ***

◆Node-to-node transparent transmission

◆Support 4 DI inputs

◆Support 2 channels of DO output

◆ Support local logic and inter-device logic

◆ Supports multiple function codes: 01, 02, 03, 04, 05, 06, 0F, 10

◆ Support active reporting of setting data

◆ Supports two working modes: host mode and slave mode. The host mode supports RS485 cascading of multiple Modbus devices.

◆ Support hardware watchdog

◆Multiple indicator lights show working status

◆ Support custom serial port heartbeat

◆ Provide two switching outputs

◆ The relay adopts photoelectric isolation

◆The relay remains in the normally open state

◆Support timing flip of relay status

◆ Support setting relay start status

◆ Support LoRa communication AES encryption

Other explanations

Buffering technology is a technology used to coordinate data transmission between devices with widely different throughput speeds, using high-performance industrial-grade chips to achieve transparent data transmission functions and low-power consumption. When multiple smart iron shoes communicate data to Lora in a short period of time, the minimum power consumption is less than 2μA; multiple I/Os are provided, which can realize digital input and output, and send data to the end, which will cause the data terminal to communicate with Lora to monitor The host sends digital analog quantities to collect pulse counting and other functions. The data speed does not match, resulting in erroneous frames, duplicate frames, and data loss. Currently, W5100 is a multifunctional single-chip network interface chip that integrates the Lora communication data terminal. There are the following problems: the data receiving and sending speeds do not match the 10/100Mbps Ethernet controller, including the full hardware TCP/IP protocol. The packet loss problem caused by the stack; under the condition of limited resources, communication terminals also have to deal with a large amount of Ethernet media transmission layer (MAC) and physical layer (PHY), and after years of market experience, there are duplicate or even erroneous and useless data. There is no error or duplication of data. W5100 provides 3 interfaces: direct parallel bus, indirect parallel bus and SPI for targeted inspection and optimization. The Lora communication data terminal bus based on circular queue buffering has a simple interface with the MCU. There is no need to consider the control of the Ethernet when using it. It is terminal-only. It combines the characteristics of the Internet of Things technology and embedded systems to realize simple processing of data terminal needs. Port programming is just like accessing external memory. Data buffering, checking and optimization make data transmission more reliable and efficient. 1 The hardware design system framework is shown in Figure 1. The Lora communication module in the Lora communication data terminal and the Lora communication module in each smart iron shoe perform wireless communication based on the Lora protocol. The smart iron shoe can send status information and alarm information to the data terminal. etc., the data terminal can send remote configuration information to the smart iron shoes; the serial port pins TXD and RXD of the MCU are connected to the serial port pins RXD and TXD of the Lora communication module respectively to perform serial communication based on the UART protocol; the serial port pins of the MCU SCLK, MOSI, MISO, and SS are respectively connected to the serial port pins SCLK, MOSI, MISO, and SS of the W5100 network interface chip to perform serial communication based on the SPI protocol. The W5100 network interface chip is shown in Figure 1. System schematic block diagram. A 10/100 to 2 workflow Ethernet controller is integrated internally and is connected to the intelligent anti-slip monitoring host through the Ethernet interface. Based on this article, a Lora communication data terminal TCP/IP protocol based on circular queue buffering is proposed for communication. The data is sent to the intelligent anti-slip monitoring host. The data terminal realizes the buffering and access of wireless intensive transmission data of smart iron shoes. The MCU uses the high-performance microcontroller launched by ST Company, STM32F103RBT6, to make the data transmission more reliable and efficient. The chip is based on the chip, which mainly includes the following three steps: ARM Cortex-M3TM 32-bit RISC core, working frequency 1) Receive data: The Lora communication module in the Lora communication data terminal receives the data sent by the smart 72MHz, two high-speed embedded memories: 20k B SRAM and 128k B SRAM . Frame flash memory, the CPU stores the data frames in the circular queue in sequence;, two I2C interfaces and two SPI interfaces, three USART interfaces, one 2) Check and optimize data: The CPU takes the data frames out of the circular queue in sequence, USB and CAN interface.The wireless communication module uses error frame-based and repeated frame inspection and optimization for data; F8L10D wireless data transmission module of Lo Ra spread spectrum technology 3) Upload data: The CPU sends the optimized data to the W5100 network interface, using the Lo Ra network Provide users with wireless data transmission functions, adopting

Chip, according to different working modes, the W5100 network interface chip sends data to the monitoring host. 3 Software design 3.1 Receiving data When the smart iron shoes send data to the Lora communication data terminal, the data terminal needs to buffer the data immediately. The specific content of the received data is shown in Figure 2, which includes the following: The CPU allocates a storage area in RAM as a buffer. Create a new circular queue, where the queue length QS, the queue head pointer f, the queue tail pointer r, and the number of elements C.

Keywords: lora digital transmission terminal