Wiznet makers

Abstract:

This paper proposed a design and implementation of the new Don ARM M0 and W5500 chip-based smart data gateway. With ARM（M052） and W5500 as the hardware core and the foreground/background systems and TCP / IP protocol as the software core, the gateway is designed for multi-type and small data to transmit, format-converse and upload to the servers data of various types on collection terminals by wireless transmission. This paper discusses the hardware design of the gateway, cutting of TCP / IP protocol and software design and implementation and the testing of hardware with the debugging tools, which is in line with the protocol requirements for communication with the remote server.

HW design:

   > NuMicro Cortex-M0 M052LBN

   > W5500 for Ethernet connection

   > 433M wireless module(F05P & J05u)

   >  3.3V regulated power supply

PS: Voltage regulator chip U2 adopts low dropout linear regulator AMS1117-3.3V. The maximum output current of this chip is 1A. The circuit uses capacitor and inductor filtering to reduce circuit noise interference as following:

NuMicro Cortex-M0 M052LBN HW Design:

433M wireless part HW design

   > F05P Transmitter

   > J05u  Receiver

Programming block diagram

SPI setting

W5500 initialization

Testing result:

The 433M wireless transmitting and receiving module has a wide operating voltage range (3~12V). When the voltage changes, the transmitting frequency basically changes. The receiving module matched with the transmitting module can receive stably without any adjustment. The module transmission distance is shown in below Table . The characteristics of the module are the transmission power is relatively large and the transmission distance is relatively long, making it more suitable for communication under harsh conditions. The antenna is erected with a 25 cm long wire. Because radio signal transmission is affected by many factors, the practical distance is only half of the nominal distance or even less.

Conclusion:

Currently, the effective transmission distance of Bluetooth is 10 meters, and the effective transmission distance of the latest Bluetooth 4.0 can reach 60 meters. The transmission distance of a single ZigBee device is usually within 100 meters (without AP). Therefore, this product has certain advantages in this aspect. The data collection gateway collects various data by connecting to wireless terminals, and then reports it to the application server. More suitable for long-distance use as small data. The Nuvoton ARM chip used is very suitable for code transplantation, and the hardware cost is relatively low.